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/cli/CLAUDE.md

@@ -1,8 +1,6 @@
 <claude-mem-context>
 # Recent Activity
 
-<!-- This section is auto-generated by claude-mem. Edit content outside the tags. -->
-
 ### Dec 10, 2025
 
 | ID | Time | T | Title | Read |

src/cli/adapters/CLAUDE.md

@@ -1,7 +0,0 @@
-<claude-mem-context>
-# Recent Activity
-
-<!-- This section is auto-generated by claude-mem. Edit content outside the tags. -->
-
-*No recent activity*
-</claude-mem-context>

src/cli/handlers/context.ts

@@ -8,11 +8,22 @@
 import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js';
 import { ensureWorkerRunning, getWorkerPort } from '../../shared/worker-utils.js';
 import { getProjectContext } from '../../utils/project-name.js';
+import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 
 export const contextHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
     // Ensure worker is running before any other logic
-    await ensureWorkerRunning();
+    const workerReady = await ensureWorkerRunning();
+    if (!workerReady) {
+      // Worker not available - return empty context gracefully
+      return {
+        hookSpecificOutput: {
+          hookEventName: 'SessionStart',
+          additionalContext: ''
+        },
+        exitCode: HOOK_EXIT_CODES.SUCCESS
+      };
+    }
 
     const cwd = input.cwd ?? process.cwd();
     const context = getProjectContext(cwd);

src/cli/handlers/file-edit.ts

@@ -8,11 +8,16 @@
 import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js';
 import { ensureWorkerRunning, getWorkerPort } from '../../shared/worker-utils.js';
 import { logger } from '../../utils/logger.js';
+import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 
 export const fileEditHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
     // Ensure worker is running before any other logic
-    await ensureWorkerRunning();
+    const workerReady = await ensureWorkerRunning();
+    if (!workerReady) {
+      // Worker not available - skip file edit observation gracefully
+      return { continue: true, suppressOutput: true, exitCode: HOOK_EXIT_CODES.SUCCESS };
+    }
 
     const { sessionId, cwd, filePath, edits } = input;
 

src/cli/handlers/observation.ts

@@ -7,11 +7,16 @@
 import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js';
 import { ensureWorkerRunning, getWorkerPort } from '../../shared/worker-utils.js';
 import { logger } from '../../utils/logger.js';
+import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 
 export const observationHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
     // Ensure worker is running before any other logic
-    await ensureWorkerRunning();
+    const workerReady = await ensureWorkerRunning();
+    if (!workerReady) {
+      // Worker not available - skip observation gracefully
+      return { continue: true, suppressOutput: true, exitCode: HOOK_EXIT_CODES.SUCCESS };
+    }
 
     const { sessionId, cwd, toolName, toolInput, toolResponse } = input;
 

src/cli/handlers/session-init.ts

@@ -8,11 +8,16 @@ import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js'
 import { ensureWorkerRunning, getWorkerPort } from '../../shared/worker-utils.js';
 import { getProjectName } from '../../utils/project-name.js';
 import { logger } from '../../utils/logger.js';
+import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 
 export const sessionInitHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
     // Ensure worker is running before any other logic
-    await ensureWorkerRunning();
+    const workerReady = await ensureWorkerRunning();
+    if (!workerReady) {
+      // Worker not available - skip session init gracefully
+      return { continue: true, suppressOutput: true, exitCode: HOOK_EXIT_CODES.SUCCESS };
+    }
 
     const { sessionId, cwd, prompt } = input;
 

src/cli/handlers/summarize.ts

@@ -10,11 +10,16 @@ import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js'
 import { ensureWorkerRunning, getWorkerPort } from '../../shared/worker-utils.js';
 import { logger } from '../../utils/logger.js';
 import { extractLastMessage } from '../../shared/transcript-parser.js';
+import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 
 export const summarizeHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
     // Ensure worker is running before any other logic
-    await ensureWorkerRunning();
+    const workerReady = await ensureWorkerRunning();
+    if (!workerReady) {
+      // Worker not available - skip summary gracefully
+      return { continue: true, suppressOutput: true, exitCode: HOOK_EXIT_CODES.SUCCESS };
+    }
 
     const { sessionId, transcriptPath } = input;
 

src/cli/hook-command.ts

@@ -3,7 +3,12 @@ import { getPlatformAdapter } from './adapters/index.js';
 import { getEventHandler } from './handlers/index.js';
 import { HOOK_EXIT_CODES } from '../shared/hook-constants.js';
 
-export async function hookCommand(platform: string, event: string): Promise<void> {
+export interface HookCommandOptions {
+  /** If true, don't call process.exit() - let caller handle process lifecycle */
+  skipExit?: boolean;
+}
+
+export async function hookCommand(platform: string, event: string, options: HookCommandOptions = {}): Promise<number> {
   try {
     const adapter = getPlatformAdapter(platform);
     const handler = getEventHandler(event);
@@ -15,11 +20,18 @@ export async function hookCommand(platform: string, event: string): Promise<void
     const output = adapter.formatOutput(result);
 
     console.log(JSON.stringify(output));
-    process.exit(result.exitCode ?? HOOK_EXIT_CODES.SUCCESS);
+    const exitCode = result.exitCode ?? HOOK_EXIT_CODES.SUCCESS;
+    if (!options.skipExit) {
+      process.exit(exitCode);
+    }
+    return exitCode;
   } catch (error) {
     console.error(`Hook error: ${error}`);
     // Use exit code 2 (blocking error) so users see the error message
     // Exit code 1 only shows in verbose mode per Claude Code docs
-    process.exit(HOOK_EXIT_CODES.BLOCKING_ERROR);  // = 2
+    if (!options.skipExit) {
+      process.exit(HOOK_EXIT_CODES.BLOCKING_ERROR);  // = 2
+    }
+    return HOOK_EXIT_CODES.BLOCKING_ERROR;
   }
 }