Replace moment.js with Temporal API (temporal-polyfill)

[Copilot]

Removes moment and moment-timezone in favor of the TC39 Temporal API via temporal-polyfill.

New utility layer

source/lib/temporal.ts — central module providing moment-compatible helpers over Temporal.ZonedDateTime:

• format(dt, token) — supports moment-style tokens (h:mma, MMM Do, LT, dddd, Do, etc.)
• Comparison helpers: isBefore, isAfter, isSame, isSameOrBefore, isSameOrAfter, isBetween
• Parsing: parseDate, parseDateFormat, parseTimeToday, parseTimeComponents
• Relative time: fromNow, relativeTo (Math.ceil rounding), calendar
• Conversion: toDate, fromDate, fromEpochMs, fromTimestamp

Migrations

• modules/: timer (useMomentTimer → useTemporalTimer, deprecated alias kept), event-type, ccc-calendar, event-list, food-menu, datepicker, add-to-device-calendar
• source/views/: building-hours, transportation/bus, streaming, menus, sis, student-orgs, stoprint
• scripts/validate-bus-schedules.mjs: moment replaced with pure-JS time parsing
• Test helpers: moment.helper.ts → temporal.helper.ts in building-hours and bus test suites

Cleanup

• Removed source/init/moment.ts and its app.tsx import
• moment, moment-timezone removed from dependencies
• CLAUDE.md updated to reference Temporal

Tests

All 200 tests pass (36 suites), TypeScript clean.

[hawkrives]

Our test coverage isn't good enough for me to trust this one. Also not thinking I like the moment compatibility layer.

Leaving as draft…