chore: Added code intelligence plugins (#5057)

* chore: Added code intelligence plugins

See:
https://code.claude.com/docs/en/discover-plugins#code-intelligence

#skip-changelog

* Coerce Claude into using LSP rather than grep

* .

* Apply suggestion from @jamescrosswell

* Remove typescript code intelligence pugin

Author: jamescrosswell

.claude/settings.json

@@ -30,5 +30,11 @@
       "Bash(mv:*)"
     ],
     "deny": []
+  },
+  "enabledPlugins": {
+    "csharp-lsp@claude-plugins-official": true,
+    "clangd-lsp@claude-plugins-official": true,
+    "jdtls-lsp@claude-plugins-official": true,
+    "swift-lsp@claude-plugins-official": true
   }
 }

AGENTS.md

@@ -159,3 +159,15 @@ AI commits MUST include:
 ```
 Co-Authored-By: <Agent Name> <agent-email-or-noreply@example.com>
 ```
+
+### Code Intelligence
+
+Prefer LSP over Grep/Read for code navigation — it's faster, precise, and avoids reading entire files:
+
+- `workspaceSymbol` to find where something is defined
+- `findReferences` to see all usages across the codebase
+- `goToDefinition` / `goToImplementation` to jump to source
+
+Use Grep only when LSP isn't available or for text/pattern searches (comments, strings, config).
+
+After writing or editing code, check LSP diagnostics and fix errors before proceeding.