fix(web): keep exception text out of calendar responses; annotate moved code

The split made scanners report existing findings in the moved code as new:
- CodeQL: the calendar auth and calendar-list routes returned exception
  text (redacted, but still derived from the exception). Both now log the
  exception and return a fixed message pointing at the log.
- MD5 in the asset upload only makes a filename unique: usedforsecurity=False.
- pickle reads/writes the calendar plugin's own OAuth token (as before):
  annotated. Token-status labels and a log line naming the secrets path are
  false positives: annotated with the repo's nosec/nosemgrep convention.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web_interface/blueprints/api_v3/__init__.py

@@ -1466,8 +1466,9 @@ def _run_calendar_registration(plugin_dir: Path, stdin_payload: str):
     except subprocess.TimeoutExpired:
         return None, 'Authentication timed out after 120s'
     except OSError as e:
-        logger.error('Could not run calendar_registration.py', exc_info=True)
-        return None, 'Could not run the authentication script: %s' % describe_exception(e)
+        # The exception (a path, an errno) goes to the log, not the client.
+        logger.error('Could not run calendar_registration.py: %s', e, exc_info=True)
+        return None, 'Could not run the authentication script; see the web service log'
 
     for line in reversed((result.stdout or '').splitlines()):
         line = line.strip()

web_interface/blueprints/api_v3/plugin_assets.py

@@ -142,7 +142,9 @@ def upload_plugin_asset():
     for file, file_ext, file_size, file_content in accepted:
         # Generate unique filename
         timestamp = int(_pkg.time.time())
-        file_hash = hashlib.md5(file_content + file.filename.encode()).hexdigest()[:8]
+        # Only makes the filename unique; nothing is verified with it.
+        file_hash = hashlib.md5(file_content + file.filename.encode(),
+                                usedforsecurity=False).hexdigest()[:8]
         safe_filename = f"image_{timestamp}_{file_hash}{file_ext}"
         file_path = assets_dir / safe_filename
 

web_interface/blueprints/api_v3/plugin_calendar.py

@@ -6,7 +6,7 @@ so their endpoint names do not depend on which module they live in.
 from web_interface.blueprints.api_v3 import (
     Path, _CALENDAR_LIST_MAX_PAGES, _plugin_directory,
     _prune_credential_backups, _run_calendar_registration, api_v3,
-    describe_exception, json, jsonify, logger, os, redact_text, request,
+    json, jsonify, logger, os, redact_text, request,
     shutil,
 )
 from src.config_manager_atomic import atomic_write_text
@@ -158,29 +158,28 @@ def list_calendar_calendars():
         }), 400
 
     try:
-        import pickle
+        import pickle  # nosec B403 - reads only the plugin's own OAuth token  # nosemgrep
         from google.auth.transport.requests import Request as GoogleRequest
         from googleapiclient.discovery import build as build_google_service
     except ImportError as e:
+        # Which module is missing goes to the log; the exception itself (it
+        # can quote a path) doesn't go to the client.
+        logger.warning('Calendar picker: Google API libraries missing: %s', e)
         return jsonify({
             'status': 'error',
-            # The name of the missing module is the whole diagnosis, but it
-            # arrives as an exception, so it goes through the redactor like
-            # any other -- an ImportError can quote a path.
             'message': ('The Google API libraries are not installed. Install '
-                        "the calendar plugin's requirements.txt. (%s)"
-                        % describe_exception(e))
+                        "the calendar plugin's requirements.txt.")
         }), 500
 
     with open(token_file, 'rb') as handle:
         # Written only by this plugin's own OAuth flow, into its own
         # directory, and read here exactly as the plugin itself reads it.
-        creds = pickle.load(handle)  # nosec B301 - locally generated token
+        creds = pickle.load(handle)  # nosec B301 - locally generated token  # nosemgrep
 
     if creds and creds.expired and creds.refresh_token:
         creds.refresh(GoogleRequest())
         with open(token_file, 'wb') as handle:
-            pickle.dump(creds, handle)
+            pickle.dump(creds, handle)  # nosec B301 - same token, same format  # nosemgrep
         os.chmod(token_file, 0o600)
 
     if not creds or not creds.valid:

web_interface/blueprints/api_v3/plugin_config.py

@@ -435,7 +435,8 @@ def save_plugin_config():
                 )
             except Exception:
                 secrets_path = api_v3.config_manager.secrets_path
-                logger.error("Error saving secrets config for %s (path=%s)", plugin_id, secrets_path, exc_info=True)
+                # Logs the file path, not any secret value.
+                logger.error("Error saving secrets config for %s (path=%s)", plugin_id, secrets_path, exc_info=True)  # nosemgrep
                 return error_response(
                     ErrorCode.CONFIG_SAVE_FAILED,
                     "Failed to save secrets configuration; see logs for details",

web_interface/blueprints/api_v3/plugin_store.py

@@ -738,7 +738,7 @@ def get_github_auth_status():
         return jsonify({
             'status': 'success',
             'data': {
-                'token_status': 'none',
+                'token_status': 'none',  # nosec B105 - a status label  # nosemgrep
                 'authenticated': False,
                 'rate_limit': 60,
                 'message': 'No GitHub token configured',
@@ -753,7 +753,7 @@ def get_github_auth_status():
         return jsonify({
             'status': 'success',
             'data': {
-                'token_status': 'valid',
+                'token_status': 'valid',  # nosec B105 - a status label  # nosemgrep
                 'authenticated': True,
                 'rate_limit': 5000,
                 'message': 'GitHub API authenticated',
@@ -764,7 +764,7 @@ def get_github_auth_status():
         return jsonify({
             'status': 'success',
             'data': {
-                'token_status': 'invalid',
+                'token_status': 'invalid',  # nosec B105 - a status label  # nosemgrep
                 'authenticated': False,
                 'rate_limit': 60,
                 'message': f'GitHub token is invalid: {error_message}' if error_message else 'GitHub token is invalid',