fix: resolve PostToolUse hook crashes and 5s latency (#1220)

Three compounding bugs caused hook failures:

1. Missing break statements in worker-service.ts switch — if async
   code threw before process.exit(), execution fell through to
   subsequent cases. Added break to all 7 cases missing them.

2. Unhandled promise rejection on main() — added .catch() that logs
   the error and exits 0 (per project exit code strategy: don't block
   Claude Code or leave Windows Terminal tabs open).

3. Redundant start commands in hooks.json — PostToolUse,
   UserPromptSubmit, and Stop groups each had a standalone start
   command that was redundant (the hook case already calls
   ensureWorkerStarted internally). The redundant start also caused
   5s latency via bun-runner.js collectStdin() timeout since Claude
   Code never closes stdin.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugin/hooks/hooks.json

@@ -43,11 +43,6 @@
     "UserPromptSubmit": [
       {
         "hooks": [
-          {
-            "type": "command",
-            "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" start",
-            "timeout": 60
-          },
           {
             "type": "command",
             "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" hook claude-code session-init",
@@ -60,11 +55,6 @@
       {
         "matcher": "*",
         "hooks": [
-          {
-            "type": "command",
-            "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" start",
-            "timeout": 60
-          },
           {
             "type": "command",
             "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" hook claude-code observation",
@@ -76,11 +66,6 @@
     "Stop": [
       {
         "hooks": [
-          {
-            "type": "command",
-            "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" start",
-            "timeout": 60
-          },
           {
             "type": "command",
             "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/bun-runner.js\" \"${CLAUDE_PLUGIN_ROOT}/scripts/worker-service.cjs\" hook claude-code summarize",