security: bandit fixes B310/B324/B110 + QuietHTTPServer (#354)

* security: fix bandit security issues (B310, B324)

- Add usedforsecurity=False to MD5 hash in gateway_watcher.py
- Add URL scheme validation to prevent file:// access in config.py
- Add URL validation to bootstrap.py health check
- Add nosec comments where runtime validation exists

* fix: handle ConnectionResetError gracefully and add debug logging

- Add QuietHTTPServer class to suppress noisy connection reset errors
  caused by clients disconnecting abruptly (fixes log spam from
  'ConnectionResetError: [Errno 54] Connection reset by peer')

- Replace silent 'pass' statements with logger.debug() calls across
  api/auth.py, api/config.py, api/gateway_watcher.py, api/models.py,
  and api/onboarding.py for better observability during troubleshooting

- All tests pass (25 passed in test_regressions.py)

* chore: add debug logging to profiles and routes modules

- Replace silent 'pass' statements with logger.debug() calls in
  api/profiles.py for better error visibility during profile switching
  and module patching

- Add logger initialization to api/routes.py

* security: fix B110 bare except/pass issues (bandit security scan)

- Replace bare except/pass patterns with logger.debug() calls
- Fixes CWE-703 (improper check/handling of exceptional conditions)
- Files affected: routes.py, state_sync.py, streaming.py, workspace.py, server.py
- All tests pass successfully

* security: bandit fixes B310/B324/B110 + QuietHTTPServer (#354)

- api/gateway_watcher.py: MD5 usedforsecurity=False (B324)
- api/config.py, bootstrap.py: URL scheme validation before urlopen (B310)
- 12 files: replace bare except/pass with logger.debug() (B110)
- server.py: QuietHTTPServer suppresses client disconnect log noise
- server.py: fix sys.exc_info() (was traceback.sys.exc_info(), impl detail)
- tests/test_sprint43.py: 19 new tests covering all security fixes
- CHANGELOG.md: v0.50.14 entry; 841 tests total (up from 822)

---------

Co-authored-by: lawrencel1ng <lawrence.ling@global.ntt>
Co-authored-by: Nathan Esquenazi <nesquena@gmail.com>

api/models.py

@@ -3,6 +3,7 @@ Hermes Web UI -- Session model and in-memory session store.
 """
 import collections
 import json
+import logging
 import time
 import uuid
 from pathlib import Path
@@ -14,6 +15,8 @@ from api.config import (
 )
 from api.workspace import get_last_workspace
 
+logger = logging.getLogger(__name__)
+
 
 def _write_session_index():
     """Rebuild the session index file for O(1) future reads."""
@@ -24,7 +27,7 @@ def _write_session_index():
             s = Session.load(p.stem)
             if s: entries.append(s.compact())
         except Exception:
-            pass
+            logger.debug("Failed to load session from %s", p)
     with LOCK:
         for s in SESSIONS.values():
             if not any(e['session_id'] == s.session_id for e in entries):
@@ -151,7 +154,7 @@ def all_sessions():
                     s['profile'] = 'default'
             return result
         except Exception:
-            pass  # fall through to full scan
+            logger.debug("Failed to load session index, falling back to full scan")
     # Full scan fallback
     out = []
     for p in SESSION_DIR.glob('*.json'):
@@ -160,7 +163,7 @@ def all_sessions():
             s = Session.load(p.stem)
             if s: out.append(s)
         except Exception:
-            pass
+            logger.debug("Failed to load session from %s", p)
     for s in SESSIONS.values():
         if all(s.session_id != x.session_id for x in out): out.append(s)
     out.sort(key=lambda s: (getattr(s, 'pinned', False), s.updated_at), reverse=True)