test(db): add self-healing tests for missing repository prompt table

- Test runtime self-healing when repository_review_prompts table is dropped

- Test migration layer self-healing for inconsistent DB state

- Verify repository listing remains functional during schema recovery

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

src/db/__tests__/migration-repository-review-prompts-heal.test.ts

@@ -0,0 +1,75 @@
+import { Database } from 'bun:sqlite';
+import { afterEach, beforeEach, describe, expect, test } from 'bun:test';
+import { randomUUID } from 'node:crypto';
+import { existsSync, mkdirSync, unlinkSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { closeDatabase, getDatabase, initDatabase } from '../database';
+
+function createInconsistentMigrationState(dbPath: string): void {
+  const db = new Database(dbPath);
+  db.exec('PRAGMA foreign_keys = ON');
+  db.exec(`
+    CREATE TABLE IF NOT EXISTS _migrations (
+      version    INTEGER PRIMARY KEY,
+      name       TEXT NOT NULL,
+      applied_at TEXT NOT NULL DEFAULT (datetime('now'))
+    )
+  `);
+
+  db.query('INSERT INTO _migrations (version, name) VALUES (?, ?)').run(
+    1,
+    'init_llm_provider_schema'
+  );
+  db.query('INSERT INTO _migrations (version, name) VALUES (?, ?)').run(
+    2,
+    'remove_legacy_review_mode'
+  );
+  db.query('INSERT INTO _migrations (version, name) VALUES (?, ?)').run(
+    3,
+    'add_repository_review_prompts'
+  );
+
+  db.close();
+}
+
+describe('migration self-heal for repository review prompts', () => {
+  let dbPath: string;
+  const savedDbPath = process.env.DATABASE_PATH;
+
+  beforeEach(() => {
+    const tmpDir = join(tmpdir(), `db-migration-heal-${randomUUID()}`);
+    mkdirSync(tmpDir, { recursive: true });
+    dbPath = join(tmpDir, 'test.db');
+    process.env.DATABASE_PATH = dbPath;
+    createInconsistentMigrationState(dbPath);
+  });
+
+  afterEach(() => {
+    closeDatabase();
+    if (savedDbPath === undefined) {
+      Reflect.deleteProperty(process.env, 'DATABASE_PATH');
+    } else {
+      process.env.DATABASE_PATH = savedDbPath;
+    }
+
+    if (existsSync(dbPath)) unlinkSync(dbPath);
+    if (existsSync(`${dbPath}-wal`)) unlinkSync(`${dbPath}-wal`);
+    if (existsSync(`${dbPath}-shm`)) unlinkSync(`${dbPath}-shm`);
+  });
+
+  test('rebuilds missing repository_review_prompts table even when migration 3 is marked applied', () => {
+    initDatabase();
+    const db = getDatabase();
+
+    const tableRow = db
+      .query("SELECT name FROM sqlite_master WHERE type = 'table' AND name = ?")
+      .get('repository_review_prompts') as { name: string } | null;
+    expect(tableRow?.name).toBe('repository_review_prompts');
+
+    const migrationCountRow = db
+      .query('SELECT COUNT(*) AS count FROM _migrations WHERE version = ?')
+      .get(3) as { count: number } | null;
+    expect(migrationCountRow?.count).toBe(1);
+  });
+});

src/db/__tests__/repository-review-prompt-repo.test.ts

@@ -3,7 +3,7 @@ import { randomUUID } from 'node:crypto';
 import { existsSync, mkdirSync, unlinkSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
-import { closeDatabase, initDatabase } from '../database';
+import { closeDatabase, getDatabase, initDatabase } from '../database';
 import { repositoryReviewPromptRepo } from '../repositories/repository-review-prompt-repo';
 
 describe('repository-review-prompt-repo', () => {
@@ -64,4 +64,30 @@ describe('repository-review-prompt-repo', () => {
       'acme/b': 'prompt-b',
     });
   });
+
+  test('self-heals missing prompt table and keeps repository listing readable', () => {
+    const db = getDatabase();
+    db.exec('DROP TABLE repository_review_prompts');
+
+    const map = repositoryReviewPromptRepo.listProjectPrompts(['acme/a']);
+    expect(map).toEqual({});
+
+    repositoryReviewPromptRepo.setProjectPrompt('acme', 'a', 'prompt-a');
+    expect(repositoryReviewPromptRepo.getProjectPrompt('acme', 'a')).toBe('prompt-a');
+  });
+
+  test('self-heals missing prompt table for direct prompt write path', () => {
+    const db = getDatabase();
+    db.exec('DROP TABLE repository_review_prompts');
+
+    const row = repositoryReviewPromptRepo.setProjectPrompt(
+      'acme',
+      'direct-write',
+      'prompt-direct'
+    );
+    expect(row.project_prompt).toBe('prompt-direct');
+    expect(repositoryReviewPromptRepo.getProjectPrompt('acme', 'direct-write')).toBe(
+      'prompt-direct'
+    );
+  });
 });