🔧 chore(standards): sync cpp playbook rules

Vendor standards live under docs/standards/playbook and are synced into .agents/cpp.

Add AGENTS.md entries so agents working in lsp-server follow the C++ ruleset and standards.

.gitattributes

@@ -23,3 +23,63 @@
 /lsp-server/test/tree_sitter_tsf/** linguist-generated=true
 !/lsp-server/test/tree_sitter_tsf/grammar.js
 **/node_modules/** linguist-vendored=true 
+
+# BEGIN playbook .gitattributes
+# Ensure all text files use UTF-8 (by convention) and LF line endings.
+# Line endings are normalized to LF in the repo and checked out as LF,
+# regardless of OS/core.autocrlf settings.
+
+# Default: detect text automatically, enforce LF on checkout/commit.
+* text=auto eol=lf
+
+# Explicit text types in this repo.
+*.tsl   text eol=lf
+*.tsf   text eol=lf
+*.md    text eol=lf
+*.txt   text eol=lf
+*.json  text eol=lf
+*.yml   text eol=lf
+*.yaml  text eol=lf
+*.toml  text eol=lf
+*.ini   text eol=lf
+*.cfg   text eol=lf
+*.xml   text eol=lf
+*.csv   text eol=lf
+*.sh    text eol=lf
+*.py    text eol=lf
+*.pyi   text eol=lf
+*.pyx   text eol=lf
+*.pxd   text eol=lf
+*.pxi   text eol=lf
+*.c     text eol=lf
+*.h     text eol=lf
+*.cc    text eol=lf
+*.cpp   text eol=lf
+*.cxx   text eol=lf
+*.hh    text eol=lf
+*.hpp   text eol=lf
+*.hxx   text eol=lf
+*.inl   text eol=lf
+*.ipp   text eol=lf
+*.ixx   text eol=lf
+*.cppm  text eol=lf
+*.mpp   text eol=lf
+*.cmake text eol=lf
+CMakeLists.txt text eol=lf
+CMakePresets.json text eol=lf
+*.clangd text eol=lf
+.clangd text eol=lf
+
+# Binary files (no line-ending conversion).
+*.png   binary
+*.jpg   binary
+*.jpeg  binary
+*.gif   binary
+*.ico   binary
+*.pdf   binary
+*.zip   binary
+*.7z    binary
+*.gz    binary
+*.tar   binary
+*.exe   binary
+# END playbook .gitattributes