feat(settings): add system theme and Kattis solve import

[cameroncuster]

Summary

• add three-way System, Light, and Dark appearance preferences with synchronous pre-paint resolution and live OS-theme updates
• persist signed-in appearance choices across devices while keeping anonymous choices local
• add immediate GitHub sign-in feedback, a secure callback progress state, and recoverable auth/logout errors
• add safe Kattis solve import from pasted IDs/URLs or local text/HTML files without scraping Kattis or requesting credentials
• re-derive tracked problem UUIDs at confirmation time under the current actor and existing RLS
• harden preference writes against concurrent theme/privacy changes, stale actor sessions, and out-of-order file reads

Behavior and safety

• existing explicit Light/Dark preferences stay explicit
• new and anonymous users default to System
• no initial light-theme flash when the OS or stored preference is dark
• Kattis preview is read-only; confirmation writes only database-derived tracked IDs
• no new dependencies

Validation

• pnpm run check
• pnpm run lint:es
• pnpm run lint
• pnpm run test:coverage — 395 passed; 98/95/98 thresholds satisfied
• pnpm run test:performance — 21,367 B raw / 1,610 B gzip
• pnpm run test:e2e — 205 passed, 7 intentional viewport/live skips

Risk analysis

• preference writes are column-specific and serialized where ordering matters
• every asynchronous save is bound to the actor that initiated it
• stale account fetches and stale local-file reads cannot overwrite newer UI state
• OAuth failure paths always return to a visible, retryable state
• theme startup remains synchronous and dependency-free

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Pull Request opened by Augment Code | View session

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Project	Deployment	Actions	Updated (UTC)
gitgud	Ready	Preview, Comment	Jul 26, 2026 3:57am

[cameroncuster]

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TL;DR: Drove the new three-way appearance preference, the Kattis solve import, and the OAuth callback/error recovery end-to-end in a real browser against a production build of the PR head served on a local mock Supabase.

Heads-up: this PR was already merged by the time the run started; findings are on the head commit 078e1b2 for the record.

🔍 Walkthrough

• Appearance is genuinely three-way and follows the OS — with the OS in light, System resolves light; flip a fresh visitor's OS to dark and System resolves dark (no light flash), exactly what mainline's light-only default couldn't do:
  

• Selecting Dark repaints the whole document to Dark Ink and persists (live "Saved"), driving data-theme from light → dark:
  

  the runtime signal behind the repaint (read from the live page after selecting Dark)

  THEME_AFTER_DARK=dark        # document.documentElement.dataset.theme after selecting "Dark"
  THEME_SYSTEM_OS_DARK=dark    # System preference under OS prefers-color-scheme: dark
  

  Both radios also carry the live "Currently resolved to …" hint (light vs dark) visible in the shots above.

• Kattis import parses pasted IDs/URLs in-browser and never contacts Kattis → gamma missing gamma <gamma-url> previews 1 matched, 1 unmatched, 2 duplicates removed:
  

  the read-only + no-scrape guarantees, and the file paths, all confirmed by the suite

  From e2e/import-solves.spec.ts (all green): paste preview asserts zero *.kattis.com requests and getSolvedWriteAttempts() === 0; a local .html file is parsed in-browser and only the DB-re-derived tracked UUID is imported (the evil.test/problems/… link is ignored); an oversized replacement clears the prior payload; the latest file wins on out-of-order reads. Confirm imports the server-derived match and is idempotent (0 newly solved on a second pass).

• OAuth callback with no session lands on a visible, retryable error rather than a dead end — home shows "Continue with GitHub" + "Couldn't open GitHub. Try again."; the suite confirms retry re-enters /auth/callback and clears the alert:
  

📋 Scope

Under test: three-way System/Light/Dark appearance with synchronous pre-paint resolution + live OS-theme follow and cross-device persistence; safe Kattis solve import from pasted IDs/URLs or local .txt/.html files (no scraping, no credentials); and clearer GitHub sign-in / callback progress + recoverable auth/logout errors.

Also covered: full hermetic suite pnpm test:e2e — 205 passed, 7 skipped (intentional viewport/live splits) on desktop + mobile, including the anonymous /settings guard, the empty-handle and provider-failure (notfound/ratelimited/fail/malformed) inline-error paths (all write nothing), and the settings a11y/keyboard/44px-target checks.

Not tested:

• SQL DDL in sql/auth/user_preferences.sql (theme default light→system, the NOT VALID theme IN ('system','light','dark') CHECK, and the new-user trigger insert) — no runtime DB surface reachable from this runner (server initdb isn't installed; the shared Supabase MCP isn't attached and any DDL would require an isolated branch). Static consistency confirmed: the DB allowlist matches the app's THEME_PREFERENCES = ['system','light','dark'] and both defaults are system.
• Live GitHub OAuth round-trip — the suite (and this run) seed a deterministic mock session by design; the opt-in SUPABASE_SMOKE=1 path is off by default.
• Pure-logic units (parser tokenizing, normalizeThemePreference, resolution) — covered by the diff's own tests/*.test.ts under CI, not re-run here.

📦 Artifacts · System/light · System/OS-dark · Dark full page · Kattis preview · Auth error

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[cameroncuster]

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Review completed with 1 suggestions.

[cameroncuster]

^{Deep Code Review Agent🐛}

This adds the theme check as NOT VALID, so any existing user_preferences row with an out-of-set theme remains in place but will start failing subsequent unrelated UPDATEs (for example changing hide_from_leaderboard) because PostgreSQL enforces not-valid checks on new row versions. Those legacy rows need an explicit rollout path; otherwise affected users cannot save unrelated preferences.

Severity: medium

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