User deletion bug:
- Store client IP in socket assigns during mount
- Access stored IP during delete event instead of connect_info
- Fixes RuntimeError when attempting to delete users
Timezone support:
- Add timezone offset maps for common timezones (no external deps)
- Implement shift_timezone/2 helper using DateTime.add/3
- Add timezone-aware format_datetime/2, format_date/2, format_iso8601/2
- Keep backwards-compatible 1-arity versions defaulting to UTC
- Add comprehensive test coverage for timezone conversions
- All tests passing (23 tests, 0 failures)
Note: Timezone offsets are standard time only (no DST handling)
Common timezones supported: America/New_York, America/Los_Angeles,
Europe/London, Europe/Paris, Asia/Tokyo, Asia/Shanghai, Australia/Sydney
- Replace JavaScript modal handlers with LiveView event bindings
- Add phx-click events for show_add_token_modal and cancel_add_token
- Convert plain HTML form to LiveView form with phx-submit
- Remove outdated window.liveSocket.execJS JavaScript code
- Add timezone parameter support to TimeHelpers functions:
- format_datetime/2 now accepts timezone and shifts DateTime
- format_date/2 now accepts timezone and shifts DateTime
- format_iso8601/2 now accepts timezone and shifts DateTime
- All helper functions fallback to UTC if timezone is invalid or nil
- Add compile-time @build_timestamp to Application module
- Create ToweropsWeb.TimeHelpers module for shared time formatting
- Update footer to display 'Last deployed Xm ago · YYYY-MM-DD HH:MM:SS UTC'
- Refactor AgentLive.Helpers to delegate to shared TimeHelpers
- Consolidate duplicate time formatting logic into single module
- Timestamp updates automatically on each build/deploy
