## Problem
Two audits of the repository (a workflow of finder, dedup and per-file verifier agents, run on 2026-10-11 against 1f4141e and again against 07f3e3c after a first round of refactoring) found dead code and features that were more machinery than the app needs: an Electron configuration-preset system with its own settings window, three copies of the about page, a hand-written `.env` parser, an "extended" system prompt nobody selected, two data migrations for formats from 2025-12 and 2026-01, a server-side example cache, type-to-confirm provider deletion, 81 unused dictionary keys, wrapper components around single call sites, and a long tail of unused exports, props, options and tests.
## Change
Every item below was either approved one by one or covered by "fix all of the others".
- **Electron:** the configuration-preset system is gone (settings window, preload, IPC, menu entry, dev watcher); `config-manager.ts` keeps only `userLocale`; `.env` files are parsed with `dotenv`. Entitlements file and a duplicate CI workflow removed; `test.yml` gets a type check and concurrency.
- **Server:** no extended prompt, no example cache, no `ENABLE_HISTORY_XML_REPLACE`, no message metadata or `hasConfig`; the connection test is one shared helper; EdgeOne loses its mock branch and model aliases; `DEBUG_LLM_PAYLOAD` logs message structure instead of payloads; Langfuse scoring helper; `apiKeyEnv` arrays kept and documented in `env.example` and the provider docs.
- **Pages:** one about page per language from a single component (old `/cn` and `/ja` URLs redirect with 308); layout uses `hasLocale`; the GitHub icon is a local component instead of `react-icons`; Cloudflare deploys without an R2 cache by default.
- **Chat and canvas:** the legacy `diagramHistory` conversion, the localStorage chat migration and the templates storage are gone; `chat-engine` reads the diagram through the context's refs; the diagram context has one tagged export path (`requestTaggedExport` / `fetchDiagramXml`); the screenshot check uses fetch + JSON and `generateText` with `Output.object`; `load-diagram` accepts `<svg:svg>` and strips the XML prolog.
- **Settings UI:** `model-selector` inlines its Dialog, Command and Tooltip; `ai-elements/model-selector`, `button-with-tooltip`, `error-toast` removed; no type-to-confirm, no footer, no `bedrockApiKey`; `use-model-config` loses the old-format migration; one reasoning component; the shimmer is CSS (no `motion`, no `@radix-ui/react-use-controllable-state`); 81 dictionary keys removed in all four languages.
- **MCP server:** `registerTool` / `ok` / `fail` replace per-tool try/catch; `syncFromBrowser`, `commitDocument`, `describePages`; the hand-written XML syntax check, unused result fields, `pickPageSelector`, `expandStyles` and the `host` attribute handling are gone; tests get a shared `setup.ts` and drive the server through the SDK client.
- **Prompt:** the web app's style rules come from the MCP drawing guide (`styleRules`), byte-identical to before.
- **Tests:** shared e2e helpers (`openApp`, `sse`, `toolCallEvents`, `chunkedReplies`); placeholder specs dropped; `settings-review-fixes` split by topic; unit tests use `vi.stubEnv`.
- **Dependencies removed:** `@xmldom/xmldom`, `remark-gfm`, `@anthropic-ai/tokenizer`, `@testing-library/user-event`, `concurrently`, `wait-on`, `eslint`, `eslint-config-next`, `@vitest/coverage-v8`, `shx`, `motion`, `@radix-ui/react-use-controllable-state`, `react-icons`.
Source lines: 74,983 before, 67,418 after (excluding lockfiles).
The last commit merges #984 (the canvas shell). Where the shell, the classic page or their tests depend on a wire format or signature this branch had changed, main's version wins (export fields of the poll response, `addHistory` signature); where main only extended code this branch restructured, main's change is carried into the new structure (`start_session`, `get_selection`, `prepareNewDiagram`, the diagram context's `requestExport`).
## Testing
- `tsc --noEmit` for the web app, `packages/mcp-server`, its shell and `electron`: clean
- `biome ci`: 0 errors (37 pre-existing warnings)
- Root `vitest run`: 719 passed; `packages/mcp-server` `vitest run`: 372 passed
- `next build`: clean
- Playwright, whole web suite on the dev server (4 workers): 280 tests, 279 passed; `language.spec.ts` "a stale offer to switch without saving does nothing once a message is being sent" failed under parallel load and passed alone, as it does on main
- Add AI provider settings to config panel (provider, model, API key, base URL)
- Support 7 providers: OpenAI, Anthropic, Google, Azure, OpenRouter, DeepSeek, SiliconFlow
- Client API keys stored in localStorage, never stored on server
- Client settings override server env vars when provided
- Skip server credential validation when client provides API key
- Bypass usage limits (request/token/TPM) when using own API key
- Add /api/config endpoint for fetching usage limits
- Add privacy notices to settings dialog, about pages, and quota toast
- Add clear settings button to reset saved API keys
- Update README files (EN/CN/JA) with BYOK documentation
Co-authored-by: dayuan.jiang <[email protected]>
* feat: add daily token limit with actual usage tracking
- Add DAILY_TOKEN_LIMIT env var for configurable daily token limit
- Track actual tokens from Bedrock API response metadata (not estimates)
- Server sends inputTokens + cachedInputTokens + outputTokens via messageMetadata
- Client increments token count in onFinish callback with actual usage
- Add NaN guards to prevent corrupted localStorage values
- Add token limit toast notification with quota display
- Remove client-side token estimation (was blocking legitimate requests)
- Switch to js-tiktoken for client compatibility (pure JS, no WASM)
* feat: add TPM (tokens per minute) rate limiting
- Add 50k tokens/min client-side rate limit
- Track tokens per minute with automatic minute rollover
- Check TPM limit after daily limits pass
- Show toast when rate limit reached
- NaN guards for localStorage values
* feat: make TPM limit configurable via TPM_LIMIT env var
* chore: restore cache debug logs
* fix: prevent race condition in TPM tracking
checkTPMLimit was resetting TPM count to 0 when checking, which
overwrote the count saved by incrementTPMCount. Now checkTPMLimit
only reads and incrementTPMCount handles all writes.
* chore: improve TPM limit error message clarity
- Add DAILY_REQUEST_LIMIT env var support in config API
- Track request count in localStorage (resets daily)
- Show friendly quota limit toast with self-host/sponsor links
- Apply limit to send, regenerate, and edit message actions
- Add Biome as formatter and linter (replaces Prettier)
- Configure Husky + lint-staged for pre-commit hooks
- Add VS Code settings for format on save
- Ignore components/ui/ (shadcn generated code)
- Remove semicolons, use 4-space indent
- Reformat all files to new style
Dayuan Jiang