feat(web): Observatory skeleton + read-only API (Day 15–16, M5 PR 1 of 3)

[furkankoykiran]

Context

Day 15–16 of 33. First PR of M5 (Observatory + MCP + pitch), inserted after a strategic replan at end of Day 14 that moved the old Day 15–16 scope (fee skim + payout graph hook) to M6 (Days 21–22). Rationale: competitor SwarmHaul has a live devnet observatory + public MCP endpoint + pitch page live on the web; Quorum has been CLI + jsonl only, so judges can't see any of the technical depth unless they git clone && uv sync. This block closes that visibility gap.

One PR for the two-day block (pivot exception to the one-PR-per-day rule — backend + frontend ship nothing demo-able if split).

What landed

• apps/api/ — read-only FastAPI adapter over the runner's jsonl artefacts. No writes, no mutation endpoints, no on-chain code. Endpoints:
  • GET /healthz, /stats, /runner/metrics
  • GET /debates/recent, /debates/{debate_id}
  • GET /shapley/leaderboard, /shapley/history
  • GET /payout/latest (null until the Day 22 graph hook)
  • WS /live/debates — 2s poll + 10s heartbeat
• apps/orchestrator/cli.py — new cli api subcommand that lazy-imports uvicorn, so cli run (the systemd runner) stays free of FastAPI imports.
• apps/web/ — Vite + React 19 + Tailwind 3.4 + TanStack Query SPA. Standalone pnpm package (own lockfile), so the existing typecheck solana-agent CI lane is untouched. Four routes:
  • / Observatory — hero stats + live agent-reasoning stdout + recent table
  • /debates, /debates/:id
  • /shapley — leaderboard + hand-rolled SVG trend (no chart lib)
  • /payout — placeholder for M6
  • Plus a live WebSocket hook with exponential-backoff reconnect and a ProtocolTelemetry footer (23 tests · devnet/fork · RFB-04/05/02 · git sha).
• 3 new offline tests (20 → 23): readers skip malformed jsonl lines gracefully; shapley history respects k; /stats endpoint shape round-trips through StatsResponse.
• CI: third job web typecheck + build, caching apps/web/pnpm-lock.yaml.

Deferred to M6 (Days 21–22)

• Fee skim on Jupiter cleanup ix + fee-vault index (old Day 15).
• _make_payout_node graph hook + payout_dry_run state field (old Day 16).
• Fork-live payout broadcast demo (new M6 scope).

/payout/latest deliberately returns {payout: null, message: "payout node lands Day 22"} until the graph hook lands.

Verification

• uv run pytest tests/test_offline.py -q → 23 passed
• uvx ruff check . && uvx ruff format --check . → clean
• cd packages/solana-agent && pnpm typecheck → clean
• cd apps/web && pnpm typecheck && pnpm build → clean (84 KB gzipped JS)
• Manual: uv run python -m apps.orchestrator.cli api --port 8081 → curl /stats returns real runner numbers (total=2, debates_count=58, shapley_rows=27 at time of smoke)
• Manual: cd apps/web && pnpm dev → 5173 proxies /api and /live to the API cleanly; all 4 routes render without console errors
• Manual: WS client receives the current latest debate on connect + a {type: "ping"} within 10s

Next PR

Days 17–18: apps/mcp-server/ — public MCP endpoint (TS, @modelcontextprotocol/sdk, 8 tools) so Claude Desktop and other agents can query Quorum debates + submit symbols.

Scope guardrails respected

No on-chain code · No new specialists · No writes to jsonl · No deploys · QUORUM_LIVE and QUORUM_PAYOUT_LIVE untouched · Ports 8000 (Divimero) and 8080 (Freqtrade) not touched.