Migrate legacy api/*.js data endpoints to sebuf RPC pattern

[koala73]

Summary

Several data-serving API endpoints use the legacy flat api/*.js pattern instead of the structured sebuf protobuf RPC pattern (api/{domain}/v1/[rpc].ts). These should be migrated for consistency, type safety, and maintainability.

Endpoints to migrate

Legacy endpoint	Target sebuf domain	Notes
api/satellites.js	intelligence/v1/list-satellites	New endpoint, should have been sebuf from the start
api/military-flights.js	military/v1/list-military-flights	Sebuf RPC exists but uses live upstream fetch instead of reading seeded Redis data
api/reverse-geocode.js	geo/v1/reverse-geocode	Utility, could be sebuf
api/gpsjam.js	intelligence/v1/get-gpsjam	Data endpoint, should follow sebuf pattern
api/oref-alerts.js	conflict/v1/list-oref-alerts	Data endpoint with WebSocket complexity
api/telegram-feed.js	intelligence/v1/list-telegram-feed	Data endpoint
api/polymarket.js	Already covered by prediction/v1/list-prediction-markets	May just need frontend migration

Endpoints that are fine as legacy

These are ops/utility endpoints that don't serve domain data:

• bootstrap.js — aggregator
• health.js, seed-health.js — ops
• register-interest.js — Convex mutation
• version.js, download.js, cache-purge.js — utility
• og-story.js, story.js — SSR/OG meta
• fwdstart.js — redirect
• rss-proxy.js — generic proxy
• opensky.js — raw proxy for desktop path
• ais-snapshot.js — AIS data proxy
• geo.js — utility

Additional context

• A test guardrail (tests/no-new-legacy-endpoints.test.mjs) has been added to prevent new legacy endpoints from being created without explicit approval
• The sebuf workflow: define messages in proto/ → buf generate → implement handler in server/worldmonitor/{domain}/v1/ → wire in handler.ts
• Each migration should update the frontend caller to use the generated sebuf client instead of raw fetch()

Acceptance criteria

• Each migrated endpoint has a proto definition, generated types, and handler
• Frontend callers updated to use sebuf client
• Legacy endpoint removed or redirected
• Health endpoint updated if Redis key names change