Add financial app

[robbiebyrd]

Financial market data. Ticker data up to the halt, the NYSE/NASDAQ closure, bond markets, and the reopening days later.

[robbiebyrd]

Plan: Finance app ("MarketWatch") — free daily data

Scope decisions

• Form factor: a Classicy app window (quote board + index tiles + market-status banner) plus a scrolling ticker-tape crawl component.
• Symbols: curated ~60–100: DJIA/S&P 500/Nasdaq/10-yr Treasury yield, the 2001-era Dow 30, and 9/11-relevant names (airlines AMR/UAL/DAL/LUV/CAL/NWAC/U, insurers AIG/MMC/MET, brokers MER/MWD/GS/LEH/BSC, defense LMT/NOC/RTN/GD, travel/hotels MAR/HLT).
• Data: daily OHLC only (free: Stooq/Kibot EOD + FRED for yields) — no paid intraday purchase. During market hours the tape moves on a deterministic synthetic intraday path pinned to each day's real open/high/low/close.
• Delivery: one static JSON generated offline, uploaded to Wasabi, served via files.911realtime.org/market/…. No backend/streamer changes.

Why daily data is enough

The product window (Sep 9–18, 2001) contains only three US equity sessions, and the market's closure is most of the story:

Virtual clock	Market state	Display
Sun 9/9 – Mon 9/10 09:29 ET	Closed (weekend)	Fri 9/7 closes, "MARKET CLOSED"
Mon 9/10 09:30–16:00	Open — normal session	Synthetic path through 9/10 OHLC
Mon 9/10 16:00 – Tue 9/11 ~08:46	Closed overnight	9/10 closes
Tue 9/11 (open never rang) → Fri 9/14	HALTED / NYSE & NASDAQ CLOSED	Frozen 9/10 closes + halt banner (longest closure since 1933)
Thu 9/13	Bond market reopens	10-yr yield resumes updating (daily step)
Mon 9/17 09:30–16:00	Reopening	Synthetic path: gap down from 9/10 close through 9/17 OHLC (Dow −684.81, −7.1%; AMR ≈ −39%, UAL ≈ −43%)
Tue 9/18 09:30–16:00	Open	Synthetic path through 9/18 OHLC

Architecture

1. Data generator (packages/tools/market-data/)

Small offline Python tool (same pattern as other tools — run once, output is immutable historical data):

• Fetch daily OHLC for the curated list from Stooq's free CSV endpoint (Kibot free EOD as fallback), date range 2001-09-04 → 2001-09-21 (need 9/7 prior closes + the three sessions).
• Fetch 10-yr Treasury yield (FRED DGS10, free CSV, no key).
• overrides.json for delisted symbols the free sources miss (AMR, UAL, LEH, MER, EK, etc.) — hand-entered from archival WSJ/NYT stock tables; the generator fails loudly on any curated symbol with no data and no override.
• Validate against known anchors (DJIA 9/10 close 9605.51 → 9/17 close 8920.70; verify from fetched data, not hardcoded).
• Emit market-data.json: symbol metadata (name, tags: index|dow30|airline|insurer|broker|defense|travel|bond), per-symbol daily bars, and a market-calendar timeline (session opens/closes, halt/closure/reopen events as UTC timestamps).
• Upload to Wasabi under market/.

2. Infra (Keeping-History/infra)

Add /market/ to the files.911realtime.org Traefik Ingress path allow-list (the nginx-s3-gateway proxy is allow-list-only). One small PR, ArgoCD syncs it.

3. Frontend app (packages/frontend/src/Applications/MarketWatch/)

Following the FlightTracker layout (co-located modules + tests):

• useMarketData.ts — fetch the JSON once at app open, cache in module scope.
• marketClock.ts — pure function: virtual-clock UTC ms → market state (closed | open | halted) + active session, using the timeline from the JSON. (Uses the virtualUtcMs pattern — strip the display tz offset.)
• syntheticIntraday.ts — pure, deterministic price path: seeded PRNG keyed on (symbol, date), Brownian-bridge-style walk pinned so price == open at 09:30, == close at 16:00, stays within [low, high] and touches both. Same minute → same price on every client/render.
• MarketWatch.tsx — app window: status banner (OPEN / TRADING HALTED / CLOSED), index tiles (DJIA, SPX, COMP, 10-yr), grouped quote board (last, change, %chg vs prior close; red/green in the Mac OS 8 palette).
• TickerTape.tsx — crawl strip using react-fast-marquee (already adopted for RadioScanner): SYMBOL price ▲/▼chg, 2001 CNBC-style. Frozen data still scrolls (as real crawls did during the closure).
• Per-minute updates driven by the classicy clock tick (era-authentic "delayed quote" cadence); the marquee animates continuously regardless.
• Icon (transparent PNG), ClassicyIcons registration, Applications-folder + desktop wiring — same checklist as Flight Tracker/Time Machine icons.

4. Testing

• marketClock state machine across every boundary in the table above (esp. 9/11 morning: open never occurs).
• syntheticIntraday: determinism, open/close pinning, high/low bounds, touches extremes.
• Component tests for banner states, quote board rendering, tape formatting; existing vitest patterns.

Sequencing

1. Generator + curated symbol list + overrides + JSON schema (validates against anchors)
2. Wasabi upload + infra allow-list PR
3. marketClock + syntheticIntraday (pure modules, TDD)
4. useMarketData + app window UI
5. Ticker tape crawl
6. Icon/registration/desktop integration
7. E2E sanity: seek clock to 9/10 14:00 (moving), 9/11 12:00 (halted), 9/17 09:35 (crash open)

Explicitly out of scope (for now)

• Paid intraday (FirstRate/Kibot 1-min) — the synthetic-path module is the single seam to swap real minute bars in later.
• Backend streamer channel — data is tiny and immutable; static JSON is the right transport.
• Broad symbol search / full-universe data.