chore(ai-workflow): require cross-browser playwright checks

.cursor/skills/implement-plan/SKILL.md

@@ -66,7 +66,7 @@ After all batches complete:
 1. Run `yarn build` to confirm everything compiles
 2. Run `yarn lint` and `yarn type-check`
 3. If the plan touched React components/hooks, run `yarn doctor`
-4. For UI changes, verify in the browser with playwright-cli
+4. For UI changes, verify in the browser with `playwright-cli` across `chrome`, `firefox`, and `webkit`, plus a mobile viewport flow in each engine when relevant
 
 ### 6. Report
 

.cursor/skills/playwright-cli/SKILL.md

@@ -6,6 +6,22 @@ allowed-tools: Bash(playwright-cli:*)
 
 # Browser Automation with playwright-cli
 
+## Cross-Browser UI Verification
+
+When using `playwright-cli` to verify rendering, styling, layout, or interactions in this repo, run the relevant flow in all three major browser engines:
+
+- `chrome` for Blink
+- `firefox` for Gecko
+- `webkit` for Safari/WebKit coverage
+
+Use separate named sessions per engine, compare the results, and record any engine-specific differences instead of treating Chromium output as sufficient.
+
+```bash
+playwright-cli -s=verify-chrome open http://example.com --browser=chrome
+playwright-cli -s=verify-firefox open http://example.com --browser=firefox
+playwright-cli -s=verify-webkit open http://example.com --browser=webkit
+```
+
 ## Quick start
 
 ```bash

.cursor/skills/review-and-merge-pr/SKILL.md

@@ -89,7 +89,7 @@ After code changes, follow repo verification rules from `AGENTS.md`:
 - run `yarn build`, `yarn lint`, and `yarn type-check`
 - run `yarn test` after adding or changing tests
 - run `yarn doctor` after React UI logic changes
-- use `playwright-cli` for UI/visual changes on desktop and mobile
+- use `playwright-cli` for UI/visual changes across `chrome`, `firefox`, and `webkit`, plus a mobile viewport flow in each engine when relevant
 
 ### 5. Report back on the PR before merging