#9628: fix: resolve tsconfig rootDir errors by separating UI config (AI-assisted)

## What & Why This PR fixes the IDE errors ("File is not under 'rootDir'") caused by the `ui` folder being included in the root [tsconfig.json](cci:7://file:///Users/leon/code/forks/openclaw/tsconfig.json:0:0-0:0) while `rootDir` is set to `src`. Since the UI project sits outside `src` and has different environment needs (DOM, Vite), I have: 1. Removed `ui/**/*` from the root [tsconfig.json](cci:7://file:///Users/leon/code/forks/openclaw/tsconfig.json:0:0-0:0) include. 2. Created a dedicated [ui/tsconfig.json](cci:7://file:///Users/leon/code/forks/openclaw/ui/tsconfig.json:0:0-0:0) configured for Lit + Vite. ## Verification - [x] `pnpm check` (root build/lint): Passed. - [x] `pnpm ui:build` (UI build): Passed. - [x] Manual: Verified red squiggles are gone in VS Code. ## Configuration Details - **Decorators**: The new [ui/tsconfig.json](cci:7://file:///Users/leon/code/forks/openclaw/ui/tsconfig.json:0:0-0:0) explicitly sets `"experimentalDecorators": true` and `"useDefineForClassFields": false` to match the project's requirement for legacy Lit decorators. ## AI Info - **Mark as AI-assisted**: Yes (Gemini / Antigravity) - **Degree of testing**: Fully tested locally (builds pass). - **Understanding**: I fully understand that this splits the TS configuration to correctly reflect the project structure (monorepo-style split between node backend and DOM frontend). <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR removes `ui/**/*` from the root `tsconfig.json` `include` (keeping `rootDir: "src"` intact) and adds a dedicated `ui/tsconfig.json` tuned for the browser/Vite/Lit environment (DOM libs, `moduleResolution: "bundler"`, decorators enabled). This resolves the IDE/tsc “file is not under rootDir” errors by ensuring the backend (`src/`) and frontend (`ui/src/`) are typechecked under separate TS projects. <h3>Confidence Score: 4/5</h3> - This PR is likely safe to merge and addresses a real TS configuration mismatch. - The change set is small and localized (tsconfig adjustments) and should resolve the reported IDE `rootDir` error. Main remaining concern is whether enabling `emitDecoratorMetadata` in the UI tsconfig is intended for the browser bundle; if not, it should be removed to avoid unwanted runtime metadata emission. - ui/tsconfig.json <!-- greptile_other_comments_section --> _{(3/5) Reply to the agent's comments like "Can you suggest a fix for this @greptileai?" or ask follow-up questions!} <!-- /greptile_comment -->