Refactor hooks codebase: reduce complexity and improve maintainability (#204)

* refactor: Clean up hook-response and new-hook files

- Removed 'PreCompact' hook type and associated logic from hook-response.ts for improved type safety.
- Deleted extensive architecture comments in new-hook.ts to streamline code readability.
- Simplified debug logging in new-hook.ts to reduce verbosity.
- Enhanced ensureWorkerRunning function in worker-utils.ts with a final health check before throwing errors.
- Added a new documentation file outlining the hooks cleanup process and future improvements.

* Refactor cleanup and user message hooks

- Updated cleanup-hook.js to improve error handling and remove unnecessary input checks.
- Simplified user-message-hook.js by removing time-sensitive announcements and streamlining output.
- Enhanced logging functionality in both hooks for better debugging and clarity.

* Refactor error handling in hooks to use centralized error handler

- Introduced `handleWorkerError` function in `src/shared/hook-error-handler.ts` to manage worker-related errors.
- Updated `context-hook.ts`, `new-hook.ts`, `save-hook.ts`, and `summary-hook.ts` to utilize the new error handler, simplifying error management and improving code readability.
- Removed repetitive error handling logic from individual hooks, ensuring consistent user-friendly messages for connection issues.

* Refactor user-message and summary hooks to utilize shared transcript parser; introduce hook exit codes

- Moved user message extraction logic to a new shared module `transcript-parser.ts` for better code reuse.
- Updated `summary-hook.ts` to use the new `extractLastMessage` function for retrieving user and assistant messages.
- Replaced direct exit code usage in `user-message-hook.ts` with constants from `hook-constants.ts` for improved readability and maintainability.
- Added `HOOK_EXIT_CODES` to `hook-constants.ts` to standardize exit codes across hooks.

* Refactor hook input interfaces to enforce required fields

- Updated `SessionStartInput`, `UserPromptSubmitInput`, `PostToolUseInput`, and `StopInput` interfaces to require `session_id`, `transcript_path`, and `cwd` fields, ensuring better type safety and clarity in hook inputs.
- Removed optional index signatures from these interfaces to prevent unintended properties and improve code maintainability.
- Adjusted related hook implementations to align with the new interface definitions.

* Refactor save-hook to remove tool skipping logic; enhance summary-hook to handle spinner stopping with error logging; update SessionRoutes to load skip tools from settings; add CLAUDE_MEM_SKIP_TOOLS to SettingsDefaultsManager for configurable tool exclusion.

* Document CLAUDE_MEM_SKIP_TOOLS setting in public docs

Added documentation for the new CLAUDE_MEM_SKIP_TOOLS configuration
setting in response to PR review feedback. Users can now discover and
customize which tools are excluded from observations.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

src/services/worker/http/routes/SessionRoutes.ts

@@ -18,6 +18,8 @@ import { BaseRouteHandler } from '../BaseRouteHandler.js';
 import { SessionEventBroadcaster } from '../../events/SessionEventBroadcaster.js';
 import { SessionCompletionHandler } from '../../session/SessionCompletionHandler.js';
 import { PrivacyCheckValidator } from '../../validation/PrivacyCheckValidator.js';
+import { SettingsDefaultsManager } from '../../../../shared/SettingsDefaultsManager.js';
+import { USER_SETTINGS_PATH } from '../../../../shared/paths.js';
 
 export class SessionRoutes extends BaseRouteHandler {
   private completionHandler: SessionCompletionHandler;
@@ -262,6 +264,17 @@ export class SessionRoutes extends BaseRouteHandler {
       return this.badRequest(res, 'Missing claudeSessionId');
     }
 
+    // Load skip tools from settings
+    const settings = SettingsDefaultsManager.loadFromFile(USER_SETTINGS_PATH);
+    const skipTools = new Set(settings.CLAUDE_MEM_SKIP_TOOLS.split(',').map(t => t.trim()).filter(Boolean));
+
+    // Skip low-value or meta tools
+    if (skipTools.has(tool_name)) {
+      logger.debug('SESSION', 'Skipping observation for tool', { tool_name });
+      res.json({ status: 'skipped', reason: 'tool_excluded' });
+      return;
+    }
+
     const store = this.dbManager.getSessionStore();
 
     // Get or create session