refactor: implement in-process worker architecture for hooks (#722)

* fix: stop generating empty CLAUDE.md files

- Return empty string instead of "No recent activity" when no observations exist
- Skip writing CLAUDE.md files when formatted content is empty
- Remove redundant "auto-generated by claude-mem" HTML comment
- Clean up 98 existing empty CLAUDE.md files across the codebase
- Update tests to expect empty string for empty input

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

* build assets

* refactor: implement in-process worker architecture for hooks

Replaces spawn-based worker startup with in-process architecture:
- Hook processes now become the worker when port 37777 is free
- Eliminates Windows spawn issues (NO SPAWN rule)
- SessionStart chains: smart-install && stop && context

Key changes:
- worker-service.ts: hook case starts WorkerService in-process
- hook-command.ts: skipExit option prevents process.exit() when hosting worker
- hooks.json: single chained command replaces separate start/hook commands
- worker-utils.ts: ensureWorkerRunning() returns boolean, doesn't block
- handlers: graceful fallback when worker unavailable

All 761 tests pass. Manual verification confirms hook stays alive as worker.

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

* context

* a

* MAESTRO: Mark PR #722 test verification task complete

All 797 tests passed (3 skipped, 0 failed) after merge conflict resolution.

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

* MAESTRO: Mark PR #722 build verification task complete

* MAESTRO: Mark PR #722 code review task complete

Code review verified:
- worker-service.ts hook case starts WorkerService in-process
- hook-command.ts has skipExit option
- hooks.json uses single chained command
- worker-utils.ts ensureWorkerRunning() returns boolean

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

* MAESTRO: Mark PR #722 conflict resolution push task complete

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

---------

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

src/services/worker-service.ts

@@ -631,11 +631,36 @@ async function main() {
       if (!platform || !event) {
         console.error('Usage: claude-mem hook <platform> <event>');
         console.error('Platforms: claude-code, cursor, raw');
-        console.error('Events: context, session-init, observation, summarize, user-message');
+        console.error('Events: context, session-init, observation, summarize');
         process.exit(1);
       }
+
+      // Check if worker is already running on port
+      const portInUse = await isPortInUse(port);
+      let startedWorkerInProcess = false;
+
+      if (!portInUse) {
+        // Port free - start worker IN THIS PROCESS (no spawn!)
+        // This process becomes the worker and stays alive
+        try {
+          logger.info('SYSTEM', 'Starting worker in-process for hook', { event });
+          const worker = new WorkerService();
+          await worker.start();
+          startedWorkerInProcess = true;
+          // Worker is now running in this process on the port
+        } catch (error) {
+          logger.failure('SYSTEM', 'Worker failed to start in hook', {}, error as Error);
+          removePidFile();
+          process.exit(0);
+        }
+      }
+      // If port in use, we'll use HTTP to the existing worker
+
       const { hookCommand } = await import('../cli/hook-command.js');
-      await hookCommand(platform, event);
+      // If we started the worker in this process, skip process.exit() so we stay alive as the worker
+      await hookCommand(platform, event, { skipExit: startedWorkerInProcess });
+      // Note: if we started worker in-process, this process stays alive as the worker
+      // The break allows the event loop to continue serving requests
       break;
     }