Document the exact response shape, query parameters, and type information
for every endpoint in server.js. This is the authoritative contract that
both Node.js and Go backends must conform to.
Covers:
- All 30+ REST endpoints with full JSON response schemas
- WebSocket message envelope and data shapes
- Shared object shapes (Packet, Observation, DecodedHeader, DecodedPath)
- Query parameter documentation with types and defaults
- Null rules, pagination conventions, error response format
- Frontend consumer matrix (which page reads which WS fields)
- Payload type and route type reference tables
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>