feat: establish unified project foundation with root config cleanup

- Archive legacy packages/, services/, server/ directories
- Update pnpm workspace to web + browser-ext
- Simplify root package.json scripts to delegate to web/
- Update turbo.json for new workspace structure
- Remove obsolete root config files (vite, tsconfig, etc.)
- Add .nvmrc, .editorconfig for consistent dev environment
- Update CI workflow to remove references to deleted packages
- Add missing dependencies (@tailwindcss/vite, tailwindcss) to web
- Add test and lint scripts to web package
- Verify pnpm install, build, and dev work correctly

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false