feat(v0211): ftsHelpers + NoteRepository.search + reviewAggregate

- ftsHelpers: sanitizeFtsQuery (FTS5 special char escape) + computeCutoff (period → KST 자정)
- search: notes_fts MATCH + status filter + rank order + sanitize + 빈 query → []
- reviewAggregate: period 별 totalCount/recentNotes(50)/tagCounts(DESC)/dueProgress(passed/pending)

tests/unit/NoteRepository.search.test.ts

@@ -0,0 +1,57 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import Database from 'better-sqlite3';
+import { runMigrations } from '../../src/main/db/migrations/index.js';
+import { NoteRepository } from '../../src/main/repository/NoteRepository.js';
+
+describe('NoteRepository.search — FTS5', () => {
+  let db: Database.Database;
+  let repo: NoteRepository;
+
+  beforeEach(() => {
+    db = new Database(':memory:');
+    db.pragma('foreign_keys = ON');
+    runMigrations(db);
+    repo = new NoteRepository(db);
+    const a = repo.create({ rawText: '오늘 월요일 회의 정리' });
+    repo.updateAiResult(a.id, { title: '회의록', summary: '월요일', tags: ['기획', '회의'], provider: 'p' });
+    const b = repo.create({ rawText: '결재 요청 본문' });
+    repo.updateAiResult(b.id, { title: '결재', summary: '요청서', tags: ['결재'], provider: 'p' });
+    const c = repo.create({ rawText: '버려진 메모' });
+    repo.setStatus(c.id, 'trashed', null);
+  });
+
+  afterEach(() => { db.close(); });
+
+  it('빈 query → 빈 배열', () => {
+    expect(repo.search('')).toEqual([]);
+    expect(repo.search('   ')).toEqual([]);
+  });
+
+  it('keyword 매칭 → hydrated Note', () => {
+    const r = repo.search('월요일');
+    expect(r.length).toBeGreaterThan(0);
+    const titles = r.map((n) => n.aiTitle);
+    expect(titles).toContain('회의록');
+  });
+
+  it('multi-token implicit AND', () => {
+    const r1 = repo.search('회의 월요일');
+    expect(r1.length).toBeGreaterThan(0);
+    const r2 = repo.search('회의 결재'); // 동시 매칭 노트 없음
+    expect(r2).toEqual([]);
+  });
+
+  it('default 는 trashed 제외', () => {
+    const r = repo.search('버려진');
+    expect(r).toEqual([]);
+  });
+
+  it('status filter 명시 시 해당 status 만', () => {
+    const r = repo.search('버려진', { status: 'trashed' });
+    expect(r.length).toBe(1);
+  });
+
+  it('FTS5 special char 안전 처리', () => {
+    expect(() => repo.search('"회의*" (월요일):')).not.toThrow();
+  });
+});