feat: ship v0.9.0 with pomodoro, achievements, and injection history

Add pomodoro timer with goal notifications, writing streak milestones, and knowledge injection logging with UI previews across AI writing flows.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/main/db/repositories/pomodoro-daily.repo.ts

@@ -0,0 +1,25 @@
+import type { DatabaseSync } from 'node:sqlite'
+import { localDateString } from '../../services/writing-date.util'
+
+export class PomodoroDailyRepository {
+  constructor(private db: DatabaseSync) {}
+
+  recordComplete(bookId: string, wordDelta: number, date = localDateString()): void {
+    this.db
+      .prepare(
+        `INSERT INTO pomodoro_daily (date, book_id, completed_count, total_words)
+         VALUES (?, ?, 1, ?)
+         ON CONFLICT(date, book_id) DO UPDATE SET
+           completed_count = completed_count + 1,
+           total_words = total_words + excluded.total_words`
+      )
+      .run(date, bookId, wordDelta)
+  }
+
+  getTodayCount(bookId: string, date = localDateString()): number {
+    const row = this.db
+      .prepare('SELECT completed_count FROM pomodoro_daily WHERE date = ? AND book_id = ?')
+      .get(date, bookId) as { completed_count: number } | undefined
+    return row?.completed_count ?? 0
+  }
+}