🐛 fix(lsp_server): disable diagnostics publishing by default

lsp-server/src/core/server.cppm

@@ -94,7 +94,14 @@ namespace lsp::core
 
         InitializeManagerHub();
         RegisterProviders();
-        RegisterDiagnosticsPublisher();
+        if (provider::kEnableDiagnosticsPublisher)
+        {
+            RegisterDiagnosticsPublisher();
+        }
+        else
+        {
+            spdlog::debug("Diagnostics publisher disabled (staged rollout)");
+        }
 
         spdlog::debug("LSP server initialized with {} providers.", dispatcher_.GetAllSupportedMethods().size());
     }

lsp-server/src/provider/manifest.cppm

@@ -88,6 +88,8 @@ import lsp.provider.trace.set_trace;
 
 export namespace lsp::provider
 {
+    inline constexpr bool kEnableDiagnosticsPublisher = false;
+
     using AllProviders = ProviderRegistry<
         completion_item::Resolve,
         Initialize,

lsp-server/test/test_provider/server_json_test.cppm

@@ -324,7 +324,7 @@ namespace lsp::test::provider
         auto expected = FindPosition(content, "function UnitFunc", false);
         assertTrue(location.range.start.line == expected.line, "Definition should resolve in document");
 
-        assertTrue(saw_diagnostics, "Server should publish diagnostics after didOpen");
+        assertTrue(!saw_diagnostics, "Server should not publish diagnostics during staged rollout");
         assertTrue(!by_id["5"].error.has_value(), "Shutdown response should not contain error");
         return result;
     }