Skip Python CI on www-only changes

Add `paths-ignore` for `www/**` and `.github/workflows/www-ci.yml`
to avoid running Python tests when only frontend code changes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ryan-williams

.github/workflows/ci.yml

@@ -2,8 +2,14 @@ name: CI
 on:
   push:
     branches: [ main ]
+    paths-ignore:
+      - 'www/**'
+      - '.github/workflows/www-ci.yml'
   pull_request:
     branches: [ main ]
+    paths-ignore:
+      - 'www/**'
+      - '.github/workflows/www-ci.yml'
   workflow_dispatch:
 
 jobs: