feat: add saved route traffic updates - #138

What

Add user-scoped saved routes and recurring traffic updates on top of the Google Maps Routes integration in #137.

Why

Common commutes should be reusable without repeatedly sharing addresses, and scheduled checks should deliver a fresh point-in-time ETA without storing traffic snapshots or implying continuous tracking.

How

• Persist Google place IDs, user-authored labels, and route preferences in owner-scoped SQLite rows
• Add save, list, check, update, delete, and recurring-update tools
• Resolve new addresses before persistence and reject partial or ambiguous endpoints
• Store versioned scheduled events containing only a route ID
• Route scheduled checks through the existing ADK reminder delivery path
• Restrict Telegram saved routes to private chats because group identity is chat-scoped
• Redact saved-route tool payloads from callbacks and observability
• Enforce per-user route and schedule limits plus a 15-minute minimum cadence

Tests

• uv run ruff format --check
• uv run ruff check --output-format=github
• uv run mypy .
• uv run pytest --cov=src --cov-report=xml --cov-report=term-missing — 1,246 passed; 100% line and branch coverage
• uv run --no-sync mkdocs build --strict
• BLACKI_EVAL_ROUTES=true uv run adk eval ... — not run because it sends prompts to the configured external model provider and requires explicit approval

Related Issues

Closes #135

Depends on #137.