refactor: wave 1 - extract leaf modules, rename catch-all files, split index.ts hooks

- Split 25+ index.ts files into hook.ts + extracted modules
- Rename all catch-all utils.ts/helpers.ts to domain-specific names
- Split src/tools/lsp/ into ~15 focused modules
- Split src/tools/delegate-task/ into ~18 focused modules
- Separate shared types from implementation
- 155 files changed, 60+ new files created
- All typecheck clean, 61 tests pass

src/hooks/delegate-task-retry/patterns.ts

@@ -0,0 +1,77 @@
+export interface DelegateTaskErrorPattern {
+  pattern: string
+  errorType: string
+  fixHint: string
+}
+
+export const DELEGATE_TASK_ERROR_PATTERNS: DelegateTaskErrorPattern[] = [
+  {
+    pattern: "run_in_background",
+    errorType: "missing_run_in_background",
+    fixHint:
+      "Add run_in_background=false (for delegation) or run_in_background=true (for parallel exploration)",
+  },
+  {
+    pattern: "load_skills",
+    errorType: "missing_load_skills",
+    fixHint:
+      "Add load_skills=[] parameter (empty array if no skills needed). Note: Calling Skill tool does NOT populate this.",
+  },
+  {
+    pattern: "category OR subagent_type",
+    errorType: "mutual_exclusion",
+    fixHint:
+      "Provide ONLY one of: category (e.g., 'general', 'quick') OR subagent_type (e.g., 'oracle', 'explore')",
+  },
+  {
+    pattern: "Must provide either category or subagent_type",
+    errorType: "missing_category_or_agent",
+    fixHint: "Add either category='general' OR subagent_type='explore'",
+  },
+  {
+    pattern: "Unknown category",
+    errorType: "unknown_category",
+    fixHint: "Use a valid category from the Available list in the error message",
+  },
+  {
+    pattern: "Agent name cannot be empty",
+    errorType: "empty_agent",
+    fixHint: "Provide a non-empty subagent_type value",
+  },
+  {
+    pattern: "Unknown agent",
+    errorType: "unknown_agent",
+    fixHint: "Use a valid agent from the Available agents list in the error message",
+  },
+  {
+    pattern: "Cannot call primary agent",
+    errorType: "primary_agent",
+    fixHint:
+      "Primary agents cannot be called via task. Use a subagent like 'explore', 'oracle', or 'librarian'",
+  },
+  {
+    pattern: "Skills not found",
+    errorType: "unknown_skills",
+    fixHint: "Use valid skill names from the Available list in the error message",
+  },
+]
+
+export interface DetectedError {
+  errorType: string
+  originalOutput: string
+}
+
+export function detectDelegateTaskError(output: string): DetectedError | null {
+  if (!output.includes("[ERROR]") && !output.includes("Invalid arguments")) return null
+
+  for (const errorPattern of DELEGATE_TASK_ERROR_PATTERNS) {
+    if (output.includes(errorPattern.pattern)) {
+      return {
+        errorType: errorPattern.errorType,
+        originalOutput: output,
+      }
+    }
+  }
+
+  return null
+}