fix(test): narrow coverage include to src/ trees to exclude e2e and config files

The previous glob `packages/**/*.{ts,tsx}` swept in Playwright e2e specs,
Playwright/Vite config files, and other non-unit-tested support files,
which could cause coverage threshold failures unrelated to source changes.
Narrowed to `packages/*/src/**/*.{ts,tsx}` so only package source trees
are measured; e2e/, playwright.config.ts, vite.config.ts etc. are excluded
by default rather than needing manual entries in the exclude list.

https://claude.ai/code/session_013coUXcACPpVfmbK9i2D86Z

Author: claude

app/vitest.config.ts

@@ -32,7 +32,9 @@ export default defineConfig({
     coverage: {
       provider: 'v8',
       // Measure all source files, not just those touched by tests.
-      include: ['packages/**/*.{ts,tsx}'],
+      // Scoped to src/ trees so Playwright e2e files, Vite/Playwright configs,
+      // and other non-unit-tested support files are excluded by default.
+      include: ['packages/*/src/**/*.{ts,tsx}'],
       exclude: [
         'packages/**/*.test.{ts,tsx}',
         'packages/**/*.d.ts',