fix: restore all code deleted/truncated by d2217531 Jules SSRF commit

Commit d2217531 (google-labs-jules SSRF fix) catastrophically deleted
11,500+ lines across 100+ files while fixing an unrelated IMAP issue.

Restored from d2217531^ (pre-bad-commit state):

Deleted files (fully restored):
- app/api/{automation,classification_rules,comments,sharing}.py
- app/middleware/upload_rate_limit.py
- app/tasks/{automation_tasks,classify_document}.py
- app/utils/{automation_hooks,classification_rules}.py
- docs/AppleAppStoreCompliance.md
- frontend/input.css, package.json, package-lock.json, tailwind.config.js
- frontend/static/js/{annotations,claim,comments,sharing}.js
- frontend/templates/{admin_connections,file_annotations,file_summary}.html
- tests/{test_api_files_comprehensive,test_auth_extended,test_sharing,
         test_comments,test_connections,test_imap_profiles,test_api_sessions,
         test_automation,test_classification_rules,test_api_advanced_filters,
         test_api_classification_rules,test_upload_rate_limit,test_api_dropbox,
         test_classify_document,test_comments_ui,test_upload_to_icloud,
         test_api_onedrive_comprehensive,test_frontend_build,test_sentry,
         test_diagnostic,test_database,test_views_dropbox,test_local_auth}.py

Truncated files (content restored):
- app/{auth,config,main,models,celery_worker,database}.py
- app/api/{__init__,api_tokens,diagnostic,dropbox,files,google_drive,
           integrations,local_auth,mobile,onedrive,pipelines,qr_auth,
           settings,url_upload}.py
- app/middleware/upload_rate_limit.py
- app/tasks/upload_to_nextcloud.py
- app/utils/{allowed_types,settings_service,settings_sync,user_scope,webhook}.py
- app/views/{base,dropbox,files,google_drive,onedrive,settings}.py
- docs/{API,AuthenticationSetup,ConfigurationGuide,DatabaseConfiguration,
        DeploymentGuide,DropboxSetup,GoogleDriveSetup,KubernetesDeployment,
        MobileApp,OneDriveSetup,ProductionReadiness,SentrySetup,
        SocialLoginSetup,UserGuide}.md
- frontend/static/{js/upload.js,styles.css}
- frontend/templates/{api_tokens,base,devices,dropbox,dropbox_callback,
                      file_view,files,google_drive,onedrive,onedrive_callback,
                      signup}.html
- frontend/translations/en.json
- migrations/env.py
- tests/{conftest,test_api_integrations,test_api_mobile,test_api_settings,
         test_api_tokens,test_audit_logs,test_duplicates,test_imap_tasks,
         test_setup_wizard,test_views_files_comprehensive}.py

Security fixes kept from post-d2217531 commits:
- app/utils/network.py: DNS SSRF fail-secure fix (06b0fced)
- app/utils/file_operations.py: path traversal fix (1018ea17)
- tests/test_imap_tasks.py: re-applied 4 is_private_ip mock patches

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>
Agent-Logs-Url: https://github.com/christianlouis/DocuElevate/sessions/51133dd8-9bec-41ab-aa10-3de753634187

app/api/diagnostic.py

@@ -21,6 +21,67 @@ _DEFAULT_REDIS_URL = "redis://localhost:6379/0"
 
 router = APIRouter()
 
+# ---------------------------------------------------------------------------
+# Unauthenticated probe endpoints for Kubernetes liveness / readiness checks.
+# These intentionally skip authentication so that kubelet can reach them
+# without credentials.  They live under /diagnostic/healthz/* so that the
+# existing authenticated /diagnostic/health endpoint is unaffected.
+# ---------------------------------------------------------------------------
+
+
+@router.get("/diagnostic/healthz/live")
+async def liveness_probe() -> JSONResponse:
+    """Lightweight liveness probe for Kubernetes.
+
+    Returns **200 OK** as long as the process is running.  Kubernetes uses
+    this to decide whether to *restart* the container — it should therefore
+    be as cheap as possible and **never** check external dependencies.
+
+    **Authentication:** None (designed for kubelet probes).
+    """
+    return JSONResponse(content={"status": "ok"}, status_code=200)
+
+
+@router.get("/diagnostic/healthz/ready")
+async def readiness_probe() -> JSONResponse:
+    """Readiness probe for Kubernetes.
+
+    Verifies that the application can serve traffic by checking the database
+    and Redis.  Kubernetes uses this to decide whether to *route traffic* to
+    the pod.
+
+    Returns **200 OK** when all critical subsystems are reachable, or
+    **503 Service Unavailable** when the database is down.
+
+    **Authentication:** None (designed for kubelet probes).
+    """
+    checks: dict[str, dict[str, str]] = {}
+    db_ok = False
+
+    # ── Database check ─────────────────────────────────────────────────
+    try:
+        with engine.connect() as conn:
+            conn.execute(text("SELECT 1"))
+        checks["database"] = {"status": "ok"}
+        db_ok = True
+    except Exception as exc:
+        logger.warning("Readiness probe: database check failed: %s", exc)
+        checks["database"] = {"status": "error", "detail": str(exc)}
+
+    # ── Redis check ────────────────────────────────────────────────────
+    try:
+        redis_url = settings.redis_url or _DEFAULT_REDIS_URL
+        r = redis_lib.from_url(redis_url, socket_connect_timeout=2, socket_timeout=2)
+        r.ping()
+        checks["redis"] = {"status": "ok"}
+    except Exception as exc:
+        logger.warning("Readiness probe: Redis check failed: %s", exc)
+        checks["redis"] = {"status": "error", "detail": str(exc)}
+
+    http_status = 503 if not db_ok else 200
+    overall = "ready" if db_ok else "not_ready"
+    return JSONResponse(content={"status": overall, "checks": checks}, status_code=http_status)
+
 
 @router.get("/diagnostic/health")
 @require_login