feat(p26): PPT 視覺審核 daily 22:00 cron — minicpm-v 自動掃當天新生 .pptx

Operation Ollama-First v5.0 / Phase 26 — PPT 自我審視整合

services/ppt_vision_service.py 擴充：
- check_ppt_file(pptx_path, max_slides=5) — 整檔視覺檢查
  • LibreOffice headless 轉每張 slide 為 png
  • 對前 N 張跑 check_image
  • 彙總 issues + 平均 confidence
  • fail-safe：LibreOffice 不在 / 轉檔失敗 → 回 skip 不阻擋
- audit_recent_ppts(reports_dir, hours=24, max_files=10)
  • 掃 reports/ 過去 24h 新生 .pptx（getmtime filter）
  • 對每個檔跑 check_ppt_file
  • 彙總總 issues
- push_ppt_audit_to_telegram(summary)
  • 有 issues 才推 Telegram（避免「無問題」洗版）
  • 每檔最多 3 張 slide / 每張 2 個 issue 列出

run_scheduler.py — 每日 22:00 cron
- run_ppt_vision_audit task wrapper
- PPT_VISION_ENABLED=false 時 service 內部 skip（不打 LLM）

設計哲學：
不動既有 5 個 prs.save() 呼叫點（risk 高）→ 改寫獨立 daily cron 集中處理
零侵入 PPT 生成主流程 / 零 risk regression / feature flag OFF 預設

部署需求：
LibreOffice headless（apt install libreoffice）— 不在則 cron task 自動 skip + log

tests/test_ppt_vision_audit.py (9 tests 全綠)
- flag OFF skip / 目錄不存在 / 無 .pptx
- 舊檔（>hours）filter / LibreOffice 不在 fail-safe
- check_ppt_file flag/missing 容錯
- Telegram 推播：無 issues 不推 / 有 issues 推

regression: ppt_vision_service 既有 6 tests 全綠

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/test_ppt_vision_audit.py

@@ -0,0 +1,149 @@
+"""
+tests/test_ppt_vision_audit.py
+─────────────────────────────────────────────────────────────────
+Operation Ollama-First v5.0 / Phase 26 — PPT 視覺審核整合驗證
+"""
+
+import os
+import tempfile
+from unittest.mock import patch, MagicMock
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def _reset_env(monkeypatch):
+    monkeypatch.delenv('PPT_VISION_ENABLED', raising=False)
+    yield
+
+
+def test_audit_disabled_by_default():
+    """flag OFF 時直接 skip（errors 含 disabled marker）"""
+    from services.ppt_vision_service import audit_recent_ppts
+
+    summary = audit_recent_ppts(reports_dir='/tmp')
+    assert summary['total_issues'] == 0
+    assert any('PPT_VISION_ENABLED=false' in e for e in summary['errors'])
+
+
+def test_audit_missing_dir(monkeypatch):
+    monkeypatch.setenv('PPT_VISION_ENABLED', 'true')
+    from services.ppt_vision_service import audit_recent_ppts
+
+    summary = audit_recent_ppts(reports_dir='/tmp/nonexistent_xyz_ppts')
+    assert summary['total_issues'] == 0
+    assert any('not found' in e for e in summary['errors'])
+
+
+def test_audit_no_recent_ppts(monkeypatch):
+    """目錄存在但無 .pptx → 0 audit"""
+    monkeypatch.setenv('PPT_VISION_ENABLED', 'true')
+    from services.ppt_vision_service import audit_recent_ppts
+
+    with tempfile.TemporaryDirectory() as tmpdir:
+        # 放一個 .txt 干擾
+        with open(os.path.join(tmpdir, 'not_ppt.txt'), 'w') as f:
+            f.write('hello')
+        summary = audit_recent_ppts(reports_dir=tmpdir)
+
+    assert summary['audited_files'] == []
+    assert summary['total_issues'] == 0
+
+
+def test_audit_filter_old_files(monkeypatch):
+    """超過 hours 視窗的舊檔不應 audit"""
+    monkeypatch.setenv('PPT_VISION_ENABLED', 'true')
+    from services.ppt_vision_service import audit_recent_ppts
+
+    with tempfile.TemporaryDirectory() as tmpdir:
+        old_path = os.path.join(tmpdir, 'old.pptx')
+        with open(old_path, 'w') as f:
+            f.write('fake')
+        # 改 mtime 到 2 天前
+        old_time = __import__('time').time() - 2 * 86400
+        os.utime(old_path, (old_time, old_time))
+
+        summary = audit_recent_ppts(reports_dir=tmpdir, hours=24)
+
+    assert summary['audited_files'] == []
+
+
+def test_check_ppt_file_libreoffice_not_installed(monkeypatch):
+    """LibreOffice 不在 → fail-safe skip 不 raise"""
+    monkeypatch.setenv('PPT_VISION_ENABLED', 'true')
+    from services.ppt_vision_service import PPTVisionService
+
+    with tempfile.NamedTemporaryFile(suffix='.pptx', delete=False) as f:
+        f.write(b'fake pptx')
+        ppt_path = f.name
+
+    try:
+        with patch('services.ppt_vision_service.subprocess.run',
+                   side_effect=FileNotFoundError('libreoffice')):
+            svc = PPTVisionService()
+            result = svc.check_ppt_file(ppt_path)
+
+        assert result['success'] is False
+        assert 'libreoffice not installed' in (result['error'] or '')
+    finally:
+        os.unlink(ppt_path)
+
+
+def test_check_ppt_file_disabled():
+    """flag OFF check_ppt_file 也 skip"""
+    from services.ppt_vision_service import PPTVisionService
+
+    with tempfile.NamedTemporaryFile(suffix='.pptx', delete=False) as f:
+        f.write(b'fake pptx')
+        ppt_path = f.name
+
+    try:
+        svc = PPTVisionService()
+        result = svc.check_ppt_file(ppt_path)
+        assert result['success'] is False
+        assert 'PPT_VISION_ENABLED=false' in (result['error'] or '')
+    finally:
+        os.unlink(ppt_path)
+
+
+def test_check_ppt_file_missing(monkeypatch):
+    monkeypatch.setenv('PPT_VISION_ENABLED', 'true')
+    from services.ppt_vision_service import PPTVisionService
+
+    svc = PPTVisionService()
+    result = svc.check_ppt_file('/tmp/this_pptx_does_not_exist_xyz.pptx')
+    assert result['success'] is False
+    assert 'not found' in (result['error'] or '')
+
+
+def test_push_telegram_skips_when_no_issues():
+    """無 issues 不推（避免靜默無問題洗版）"""
+    from services.ppt_vision_service import push_ppt_audit_to_telegram
+
+    summary = {'total_issues': 0, 'audited_files': [{'path': 'a.pptx', 'issues': 0}]}
+    assert push_ppt_audit_to_telegram(summary) is False
+
+
+def test_push_telegram_with_issues():
+    """有 issues 才推 Telegram"""
+    from services.ppt_vision_service import push_ppt_audit_to_telegram
+
+    summary = {
+        'total_issues': 3,
+        'audited_files': [
+            {
+                'path': '/tmp/test.pptx',
+                'slides_checked': 2,
+                'issues': 3,
+                'issues_by_slide': [(1, ['⚠️ 圖表被切', '⚠️ 文字溢出']), (2, ['⚠️ 配色衝突'])],
+            },
+        ],
+    }
+    with patch('services.telegram_templates._send_telegram_raw') as mock_send:
+        result = push_ppt_audit_to_telegram(summary)
+
+    assert result is True
+    mock_send.assert_called_once()
+    msg = mock_send.call_args[0][0]
+    assert 'PPT 視覺審核' in msg
+    assert '3 issues' in msg or '3' in msg