ruff (#169)

* polish: streamline nav, extract inline styles, improve tablet UX

- Restructure desktop nav from 8+ flat links + overflow dropdown into
  5 grouped dropdowns (Core, Agents, Intel, System, More) matching
  the mobile menu structure to reduce decision fatigue
- Extract all inline styles from mission_control.html and base.html
  notification elements into mission-control.css with semantic classes
- Replace JS-built innerHTML with secure DOM construction in
  notification loader and chat history
- Add CONNECTING state to connection indicator (amber) instead of
  showing OFFLINE before WebSocket connects
- Add tablet breakpoint (1024px) with larger touch targets for
  Apple Pencil / stylus use and safe-area padding for iPad toolbar
- Add active-link highlighting in desktop dropdown menus
- Rename "Mission Control" page title to "System Overview" to
  disambiguate from the chat home page
- Add "Home — Timmy Time" page title to index.html

https://claude.ai/code/session_015uPUoKyYa8M2UAcyk5Gt6h

* fix(security): move auth-gate credentials to environment variables

Hardcoded username, password, and HMAC secret in auth-gate.py replaced
with os.environ lookups. Startup now refuses to run if any variable is
unset. Added AUTH_GATE_SECRET/USER/PASS to .env.example.

https://claude.ai/code/session_015uPUoKyYa8M2UAcyk5Gt6h

* refactor(tooling): migrate from black+isort+bandit to ruff

Replace three separate linting/formatting tools with a single ruff
invocation. Updates tox.ini (lint, format, pre-push, pre-commit envs),
.pre-commit-config.yaml, and CI workflow. Fixes all ruff errors
including unused imports, missing raise-from, and undefined names.
Ruff config maps existing bandit skips to equivalent S-rules.

https://claude.ai/code/session_015uPUoKyYa8M2UAcyk5Gt6h

---------

Co-authored-by: Claude <noreply@anthropic.com>

src/timmy/tools.py

@@ -15,10 +15,12 @@ from __future__ import annotations
 
 import logging
 import math
+from collections.abc import Callable
 from dataclasses import dataclass, field
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
-from typing import Any, Callable
+
+from config import settings
 
 logger = logging.getLogger(__name__)
 
@@ -79,7 +81,7 @@ def _track_tool_usage(agent_id: str, tool_name: str, success: bool = True) -> No
     _TOOL_USAGE[agent_id].append(
         {
             "tool": tool_name,
-            "timestamp": datetime.now(timezone.utc).isoformat(),
+            "timestamp": datetime.now(UTC).isoformat(),
             "success": success,
         }
     )
@@ -497,7 +499,7 @@ def create_full_toolkit(base_dir: str | Path | None = None):
 
             # Spawn as a background task on the running event loop
             try:
-                loop = asyncio.get_running_loop()
+                asyncio.get_running_loop()
                 future = asyncio.ensure_future(_launch())
                 task_id = id(future)
                 logger.info("Agentic loop started (task=%s)", task[:80])
@@ -507,8 +509,8 @@ def create_full_toolkit(base_dir: str | Path | None = None):
                 return f"Task completed: {result.summary}"
 
             return (
-                f"Background task started. I'll execute this step-by-step "
-                f"and stream progress updates. You can monitor via the dashboard."
+                "Background task started. I'll execute this step-by-step "
+                "and stream progress updates. You can monitor via the dashboard."
             )
 
         toolkit.register(plan_and_execute, name="plan_and_execute")