feat(keyword-detector): show toast notification when ultrawork mode is activated (#393)

* feat(keyword-detector): show toast notification when ultrawork mode is activated

When users trigger ultrawork mode (via 'ultrawork' or 'ulw' keywords), a toast
notification now appears to confirm the mode is active. The notification is
shown once per session to avoid spamming.

Changes:
- Add detectKeywordsWithType() to identify which keyword type triggered
- Show 'Ultrawork Mode Activated' toast with success variant
- Track notified sessions to prevent duplicate toasts

Closes #392

* fix(keyword-detector): fix index bug in detectKeywordsWithType and add error logging

- Fix P1: detectKeywordsWithType now maps before filtering to preserve
  original KEYWORD_DETECTORS indices. Previously, the index used was from
  the filtered array, causing incorrect type assignment (e.g., 'search'
  match would incorrectly return 'ultrawork' type).

- Fix P2: Replace silent .catch(() => {}) with proper error logging using
  the log function for easier debugging when toast notifications fail.

---------

Co-authored-by: sisyphus-dev-ai <sisyphus-dev-ai@users.noreply.github.com>

src/index.ts

@@ -237,7 +237,7 @@ const OhMyOpenCodePlugin: Plugin = async (ctx) => {
       })
     : null;
   const keywordDetector = isHookEnabled("keyword-detector")
-    ? createKeywordDetectorHook()
+    ? createKeywordDetectorHook(ctx)
     : null;
   const agentUsageReminder = isHookEnabled("agent-usage-reminder")
     ? createAgentUsageReminderHook(ctx)