📦 deps(thirdparty): update snapshots

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+# Instruments Trace Analysis
+
+Use this reference whenever the user references an Xcode Instruments `.trace`
+file. A target SwiftUI source file is **optional** — if provided, you can
+cite specific lines; without one, the trace still surfaces view names,
+hot symbols, and high-severity events that tell the user where to look.
+
+The bundled parser reads five lanes for SwiftUI responsiveness (Time
+Profiler, Hangs, Animation Hitches, SwiftUI updates, and the SwiftUI
+cause graph) and exposes three discovery modes (`--list-logs`,
+`--list-signposts`, `--fanin-for`) plus a `--window` flag so the agent
+can focus analysis on a precise slice of the trace.
+
+## When to invoke
+
+Any of these signals:
+
+- Message contains a path ending in `.trace`.
+- User mentions "hangs", "hitches", "jank", "slow view", or performance
+  issues alongside an Instruments recording.
+- User asks to focus analysis "after / before / between / during" a log
+  message or signpost.
+
+Triggering does **not** require a SwiftUI source file. If one is present
+you'll ground recommendations in specific lines; if not, base them on the
+view names and symbols the trace reveals.
+
+## The three CLI modes
+
+The scripts live alongside this skill at `scripts/` and need only the
+Python 3 stdlib + `xctrace` (ships with Xcode at `/usr/bin/xctrace`).
+
+### 1. Full analysis (default)
+
+```bash
+python3 "${SKILL_DIR}/scripts/analyze_trace.py" \
+  --trace "/path/to/file.trace" \
+  --top 10 --top-hitches 5 \
+  [--window START_MS:END_MS] \
+  --json-only
+```
+
+- `--json-only` gives you structured data; omit for JSON + markdown
+  summary; `--markdown-only` is for pasting a digest into the chat.
+- `--output <path>` writes `<path>.json` and `<path>.md` instead of stdout.
+- `--window START_MS:END_MS` (optional) restricts every lane and every
+  correlation to that time slice.
+- `--run N` selects a specific run when the trace contains more than one
+  recording session. Single-run traces don't need it; multi-run traces
+  require it and will error with the available run numbers if omitted.
+  Use `--list-runs` to dump per-run metadata (template, duration,
+  start/end dates, schemas) before analyzing.
+
+### 2. `--list-logs` — find os_log timestamps
+
+```bash
+python3 "${SKILL_DIR}/scripts/analyze_trace.py" --trace <path> --list-logs \
+  [--log-subsystem com.myapp.net] \
+  [--log-category "Network"] \
+  [--log-type Fault] \
+  [--log-message-contains "loaded feed"] \
+  [--log-limit 10] \
+  [--window START_MS:END_MS]
+```
+
+Returns JSON `{ "logs": [...], "count": N }` where each log entry includes
+`time_ms`, `type`, `subsystem`, `category`, `process`, and the formatted
+`message` (with args substituted) + raw `format_string`. All filters are
+AND-combined; `--log-message-contains` is case-insensitive substring match.
+
+### 3. `--list-signposts` — find signpost intervals
+
+```bash
+python3 "${SKILL_DIR}/scripts/analyze_trace.py" --trace <path> --list-signposts \
+  [--signpost-name-contains "ImageDecode"] \
+  [--signpost-subsystem com.myapp.feed] \
+  [--signpost-category "Rendering"] \
+  [--window START_MS:END_MS]
+```
+
+Returns JSON `{ "intervals": [...], "events": [...] }`. Intervals are
+paired `begin`/`end` signposts with `start_ms`, `end_ms`, `duration_ms`,
+`name`, `subsystem`, `category`, `process`, `signpost_id`. Single-point
+events (and any unpaired begins) go into `events`. All filters are
+AND-combined; `--signpost-name-contains` is case-insensitive substring
+match.
+
+### 4. `--fanin-for` — who keeps invalidating this view?
+
+```bash
+python3 "${SKILL_DIR}/scripts/analyze_trace.py" --trace <path> \
+  --fanin-for "TextStyleModifier" \
+  [--window START_MS:END_MS] \
+  [--top 10]
+```
+
+Returns JSON `{ "matches": [...] }`. Each match names a destination node
+whose fmt string contains the substring (case-insensitive) and lists its
+top incoming source nodes ranked by edge count. Use this after the
+`swiftui` lane names an expensive view and you want to know *why it keeps
+being invalidated*. For the example above, the top source is
+`closure #1 in UserDefaultObserver.Target.GraphAttribute.send()` — the
+canonical signature of an `@AppStorage` / `UserDefaults` feedback storm.
+
+## Composition pattern — scoping to a slice
+
+When the user says something like "focus on X", "between A and B", or
+"during signpost Y", compose the three modes:
+
+1. **Discover** — call `--list-logs` or `--list-signposts` with filters
+   that match the user's description. Pick the right entries.
+2. **Build the window** — take `time_ms` (logs) or `start_ms`/`end_ms`
+   (intervals) and form `--window START:END`.
+3. **Analyse** — call the default mode with `--window`.
+
+Examples:
+
+- *"Focus on the section after the log saying 'loaded feed'."*
+  → `--list-logs --log-message-contains "loaded feed"`, take the entry's
+  `time_ms`, set window = `[that_ms, end_of_trace_ms]` (or use the trace
+  `duration_s × 1000`).
+- *"Between the 'begin-sync' log and the 'done-sync' log."*
+  → Two `--list-logs` calls (or one with a broader filter), pick the two
+  timestamps, set window = `[first, second]`.
+- *"During the signpost 'ImageDecode'."*
+  → `--list-signposts --signpost-name-contains "ImageDecode"`, pick the
+  interval, set window = `[start_ms, end_ms]`.
+
+## JSON shape
+
+```json
+{
+  "trace": "...",
+  "xctrace_version": "26.4 (...)",
+  "template": "SwiftUI",
+  "duration_s": 14.83,
+  "schemas_available": [...],
+  "lanes": [
+    { "lane": "time-profiler", "available": true, "schema_used": "time-profile",
+      "metrics": { "total_samples": N, "total_weight_ms": ms, "processes": [...] },
+      "top_offenders": [ { "symbol", "weight_ms", "percent", "samples", "thread" } ] },
+    { "lane": "hangs", "available": true, "schema_used": "potential-hangs",
+      "metrics": { "count", "total_duration_ms", "worst_duration_ms",
+                   "severity_buckets": {"lt_250ms","250ms_1s","gt_1s"} },
+      "top_offenders": [ { "start_ms", "duration_ms", "hang_type", "thread" } ] },
+    { "lane": "hitches", "available": true, "schema_used": "hitches",
+      "metrics": { "count", "total_hitch_ms", "worst_hitch_ms",
+                   "narrative_breakdown": {...}, "system_hitches", "app_hitches" },
+      "top_offenders": [ { "start_ms", "hitch_duration_ms", "narrative", "is_system" } ] },
+    { "lane": "swiftui", "available": true, "schemas_used": [...],
+      "metrics": { "total_events", "unique_views", "total_duration_ms",
+                   "severity_breakdown": {"Very Low":N,"Moderate":N,"High":N},
+                   "update_type_breakdown": {"View Body Updates":N, ...} },
+      "top_offenders": [ { "view", "total_ms", "count", "avg_ms" } ],
+      "high_severity_events": [ { "view", "severity", "duration_ms", "category",
+                                   "update_type", "description" } ] },
+    { "lane": "swiftui-causes", "available": true, "schema_used": "swiftui-causes",
+      "metrics": { "total_edges", "unique_sources", "unique_destinations",
+                   "top_labels": {...} },
+      "top_sources":      [ { "source", "edges", "top_destinations": [...] } ],
+      "top_destinations": [ { "destination", "edges", "top_sources":      [...] } ] }
+  ],
+  "correlations": [
+    {
+      "trigger": { "lane": "hangs"|"hitches", "start_ms", "end_ms", "duration_ms",
+                   "hang_type"|"frame_duration_ms" },
+      "time_profiler_main_thread": {
+        "samples_in_window": N, "samples_on_main": M,
+        "main_running_coverage_pct": 0–100,
+        "hot_symbols": [ { "symbol", "samples", "weight_ms", "percent_of_main" } ]
+      },
+      "swiftui_overlapping_updates": [ { "view", "duration_ms", "start_ms" } ]
+    }
+  ]
+}
+```
+
+## Interpretation guide
+
+### `main_running_coverage_pct` is the key diagnostic
+
+Time Profiler samples the main thread every ~1ms. For a correlation window
+of `N` ms, you'd expect ~`N` main-thread running samples if main were fully
+CPU-bound. Coverage is the ratio of observed main-thread samples to that
+expectation.
+
+- **< 25% coverage** → main thread was **blocked** (I/O, lock, sync XPC,
+  `Task.sleep`, waiting on an actor-isolated call). The `hot_symbols` you
+  do see are the moments main *was* executing — look there for the code
+  that *initiates* the blocking work, not the work itself. Common fix:
+  move to a background executor / `nonisolated` / `Task.detached`.
+- **≥ 75% coverage** → main was **CPU-bound** the whole time. `hot_symbols`
+  point directly at the expensive work. Common fixes: hoist computation
+  out of view bodies, cache derived values, avoid per-frame allocation,
+  debounce `onChange`.
+- **25–75%** → mix. Usually computation plus intermittent I/O; show both
+  hot symbols and note that main was partially blocked.
+
+### High-severity SwiftUI events → reference routing
+
+When `swiftui.high_severity_events[].description` is one of:
+
+| description      | Likely cause              | Route to                            |
+|------------------|---------------------------|-------------------------------------|
+| `onChange`       | Expensive `.onChange` body | `references/performance-patterns.md`, `references/state-management.md` |
+| `Gesture`        | Heavy gesture handler     | `references/performance-patterns.md` |
+| `Action Callback`| Button/tap handler work   | `references/performance-patterns.md` |
+| `Update`         | View body recomputation   | `references/view-structure.md`, `references/performance-patterns.md` |
+| `Creation`       | View init cost            | `references/view-structure.md`      |
+| `Layout`         | GeometryReader churn      | `references/layout-best-practices.md` |
+
+### Mapping trace findings to source code
+
+If the user gave you a specific file, use it to confirm/cite. If they didn't, the trace itself tells you which views and symbols to look up.
+
+1. **From `swiftui.top_offenders` and `high_severity_events`**, use the
+   `view` string as your search key. If a target file is open, grep it;
+   if not, recommend the user grep their project for that type or the
+   module name. A partial match (prefix / generic stripping) means it's
+   probably a subview.
+2. **From `correlations[].time_profiler_main_thread.hot_symbols`**, treat
+   symbols starting with the user's module name (or in Swift free-function
+   form) as candidates. System frames (`swift_`, `dyld`, `objc_`, `CA*`,
+   `CF*`, `NS*`, `__open`, `pthread*`) identify *what* the code was doing
+   but the user-code caller one frame up is typically what to fix — say
+   so and, if you can, suggest searching the project for callers of the
+   equivalent Swift API (e.g. `__open` → `FileHandle` / `Data(contentsOf:)` /
+   `JSONDecoder.decode(from: Data)` sites).
+3. **From `hitches[].narrative`**, Apple pre-attributes each hitch. The
+   string `"Potentially expensive app update(s)"` means SwiftUI blamed the
+   app (so user code is in scope); absence of narrative usually means it
+   was a system hitch or below the threshold.
+4. **Correlating hitches with SwiftUI updates**: the
+   `swiftui_overlapping_updates` list on each hitch names the views that
+   were actively rendering when the frame dropped. Prioritise those.
+
+### Cause graph: finding *why* updates keep happening
+
+The `swiftui` lane tells you *what* is expensive; the `swiftui-causes`
+lane tells you *why* it keeps being triggered. Each edge is "source node
+propagated to destination node" in SwiftUI's attribute graph.
+
+Signatures to watch for in `top_sources`:
+
+- **`closure #1 in UserDefaultObserver.Target.GraphAttribute.send()`** —
+  an `@AppStorage` / `UserDefaults` write is fanning out to every reader.
+  If the destination list contains multiple `@AppStorage <Type>.<prop>`
+  entries with thousands of edges each, you have a feedback storm. Fix
+  by reading each key once at a high level and passing values down, or
+  wrapping settings in a single `@Observable` so only genuine readers
+  invalidate. Route to `references/state-management.md` and
+  `references/performance-patterns.md`.
+- **`EnvironmentWriter: …`** with thousands of edges — a modifier (often
+  `.hoverEffect`, custom environment keys) is applied too widely and
+  being re-installed during every layout pass. Route to
+  `references/view-structure.md`.
+- **`View Creation / Reuse`** as the #1 source — the hierarchy is
+  replacing children rather than mutating in place. Look for ID
+  instability (missing/unstable `.id(…)` on ForEach, type-erased
+  `AnyView` wrappers, conditional structure swaps). Route to
+  `references/list-patterns.md` and `references/view-structure.md`.
+
+When a specific view in `swiftui.high_severity_events` keeps showing up,
+run `--fanin-for "<view name>"` to see the ranked list of sources
+invalidating it.
+
+### Picking targets from a full-trace analysis
+
+Prioritise from most actionable to least:
+
+1. **Any `hangs` with `main_running_coverage_pct < 25%`** — these are
+   blocking-I/O smells; nearly always fixable by moving work off-main.
+2. **Any `hangs` with `main_running_coverage_pct ≥ 75%`** — CPU-bound
+   main-thread work; fix the top `hot_symbols`.
+3. **`swiftui-causes.top_sources` with > ~1k edges** — structural
+   invalidation bugs (feedback storms, over-applied modifiers). These
+   are often cheaper to fix than per-view optimisations and collapse
+   many downstream high-severity updates at once.
+4. **`hitches` with `narrative == "Potentially expensive app update(s)"`**
+   and overlapping `swiftui_overlapping_updates` — specific views to
+   restructure.
+5. **`swiftui.high_severity_events`** — `onChange`, `Gesture`, or `Action
+   Callback` with `duration_ms > ~16` are frame-dropping handlers. For
+   any that keep firing, run `--fanin-for` to find the source.
+6. **`swiftui.top_offenders`** — heaviest views by total body time, even
+   without triggering hitches; candidates for view extraction or
+   memoisation (`equatable`, `@ViewBuilder` extraction).
+
+## Recommended output format for the user
+
+After running the parser, structure your response as:
+
+1. **One-line summary** — "Found N hangs, worst Wms; K hitches; J high-severity SwiftUI updates."
+2. **Root-cause findings** — per prioritised target (see above), one paragraph with the trace evidence (coverage %, hot symbol, overlapping view) and a citation from `references/…` for the fix pattern.
+3. **Plan** — numbered, file-specific edits. Cite line numbers in the user's Swift file when you know them. Don't edit the file unless the user asked for edits.