feat: interface PIN, bulk disposition tagging, Google Drive delta scan, OCR memory fixes

- Interface PIN: optional session-level auth gate for the main scanner UI
  (Settings → Security → Interface PIN). Salted SHA-256 in config.json,
  rate-limited (5 attempts/5 min per IP). /view and viewer auth exempt.
  New /login page, before_request hook, GET/POST/DELETE /api/interface/pin,
  POST /api/interface/pin/verify, POST /api/interface/logout.

- Bulk disposition tagging: Select mode (filter bar "Vælg" button) reveals
  per-card checkboxes. Bulk tag bar at bottom of grid; POST /api/db/disposition/bulk.
  Disposition stats bar (total · unreviewed · retain · delete · % reviewed)
  updates after every save.

- Google Drive delta scan: uses Drive Changes API when delta is enabled.
  Per-user token stored as gdrive:{email} in delta.json. Load-then-merge
  save avoids racing with concurrent M365 token writes.

- PDF OCR OOM fix: render one page at a time with convert_from_path
  (first_page=N, last_page=N). Added _ocr_mem_ok() psutil guard (500 MB
  threshold) before each page render across scan_pdf, redact_fitz_pdf,
  redact_pdf.

- Email test message translation fix: routes/email.py returns structured
  {ok, method, recipients} instead of a hardcoded English string;
  scheduler.js builds the translated message client-side.

- Docs: CHANGELOG, README, TODO, MANUAL-EN, MANUAL-DA all updated.
  Lang files (en/da/de) extended with bulk, interface PIN, and SMTP keys.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

routes/email.py

@@ -147,8 +147,7 @@ def smtp_test():
     if state.connector and state.connector.is_authenticated():
         try:
             _send_email_graph(subject, body_html, recipients)
-            return jsonify({"ok": True,
-                            "message": f"Test email sent via Microsoft Graph to {', '.join(recipients)}"})
+            return jsonify({"ok": True, "method": "graph", "recipients": recipients})
         except Exception as graph_err:
             graph_error_str = str(graph_err)
     else:
@@ -193,8 +192,8 @@ def smtp_test():
             if username and password:
                 server.login(username, password)
             server.sendmail(from_addr, recipients, msg.as_string())
-        suffix = " (⚠ Graph also failed — Mail.Send permission not granted)" if graph_error_str else ""
-        return jsonify({"ok": True, "message": f"Test email sent via SMTP to {', '.join(recipients)}{suffix}"})
+        return jsonify({"ok": True, "method": "smtp", "recipients": recipients,
+                        "graph_also_failed": bool(graph_error_str)})
     except Exception as smtp_err:
         err_str = str(smtp_err)
         _h = host.lower()