[AFBH-1740] : Normalize public URL handling in dev server

[SravanKumar2305]

Motivation

The dev server currently allows publicUrl values without trailing slashes (e.g., http://localhost:8080 or /assets), which can result in malformed asset URLs like localhost:8080assets.json instead of localhost:8080/assets.json. This leads to broken asset loading in the development environment.

Changes

• Added URL normalization that affects both dev server routing and bundled asset URLs
• Added a new feature flag normalizePublicUrlTrailingSlash that automatically appends a trailing slash to publicUrl values in the dev server when enabled
• The feature flag is enabled by default in test environment but disabled in production to maintain backward compatibility
• Added integration tests to verify the normalization works correctly for both relative paths (e.g., /assets) and full URLs (e.g., http://localhost:8080)
• Updated both packages/core/cli/src/normalizeOptions.ts and packages/core/feature-flags/src/index.ts

Checklist

• Existing or new tests cover this change
• There is a changeset for this change, or one is not required

---

Changeset :

This change adds a new feature flag normalizePublicUrlTrailingSlash that, when enabled, automatically adds a trailing slash to publicUrl values in the dev server. This prevents issues where URLs without trailing slashes (e.g., http://localhost:8080 or /assets) could result in malformed asset URLs like localhost:8080assets.json instead of localhost:8080/assets.json.

The feature flag is disabled by default to maintain backward compatibility. Enable it with:

featureFlags: {
  normalizePublicUrlTrailingSlash: true;
}

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[changeset-bot]

🦋 Changeset detected

Latest commit: 81cc853

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 112 packages

Name	Type
@atlaspack/cli	Patch
@atlaspack/feature-flags	Patch
@atlaspack/integration-tests	Patch
atlaspack	Patch
@atlaspack/inspector	Patch
@atlaspack/inspector-frontend	Patch
@atlaspack/bundler-experimental	Patch
@atlaspack/bundler-default	Patch
@atlaspack/cache	Patch
@atlaspack/core	Patch
@atlaspack/fs	Patch
@atlaspack/graph	Patch
@atlaspack/types-internal	Patch
@atlaspack/utils	Patch
@atlaspack/optimizer-inline-requires	Patch
@atlaspack/packager-html	Patch
@atlaspack/packager-js	Patch
@atlaspack/reporter-cli	Patch
@atlaspack/reporter-compiled-css-in-js-migration-map	Patch
@atlaspack/reporter-conditional-manifest	Patch
@atlaspack/runtime-js	Patch
@atlaspack/runtime-react-refresh	Patch
@atlaspack/transformer-compiled-css-in-js	Patch
@atlaspack/transformer-css	Patch
@atlaspack/transformer-html	Patch
@atlaspack/transformer-js	Patch
@atlaspack/transformer-react-refresh-wrap	Patch
@atlaspack/transformer-tokens	Patch
@atlaspack/node-resolver-core	Patch
@atlaspack/config-default	Patch
@atlaspack/test-utils	Patch
@atlaspack/query	Patch
@atlaspack/config-webextension	Patch
@atlaspack/register	Patch
@atlaspack/bundle-stats	Patch
@atlaspack/optimizer-image	Patch
@atlaspack/reporter-bundle-stats	Patch
@atlaspack/transformer-image	Patch
@atlaspack/package-manager	Patch
@atlaspack/link	Patch
@atlaspack/codeframe	Patch
@atlaspack/logger	Patch
@atlaspack/plugin	Patch
@atlaspack/profiler	Patch
@atlaspack/types	Patch
@atlaspack/workers	Patch
@atlaspack/packager-css	Patch
@atlaspack/reporter-bundle-buddy	Patch
@atlaspack/resolver-tesseract	Patch
@atlaspack/transformer-less	Patch
@atlaspack/transformer-postcss	Patch
@atlaspack/transformer-xml	Patch
@atlaspack/ts-utils	Patch
@atlaspack/optimizer-blob-url	Patch
@atlaspack/optimizer-css	Patch
@atlaspack/optimizer-data-url	Patch
@atlaspack/optimizer-svgo	Patch
@atlaspack/optimizer-swc	Patch
@atlaspack/optimizer-terser	Patch
@atlaspack/packager-raw-url	Patch
@atlaspack/packager-svg	Patch
@atlaspack/packager-webextension	Patch
@atlaspack/packager-xml	Patch
@atlaspack/reporter-build-metrics	Patch
@atlaspack/reporter-bundle-analyzer	Patch
@atlaspack/reporter-dev-server-sw	Patch
@atlaspack/reporter-dev-server	Patch
@atlaspack/reporter-json	Patch
@atlaspack/reporter-lsp	Patch
@atlaspack/reporter-sourcemap-visualiser	Patch
@atlaspack/reporter-tracer	Patch
@atlaspack/resolver-glob	Patch
@atlaspack/runtime-browser-hmr	Patch
@atlaspack/runtime-service-worker	Patch
@atlaspack/runtime-webextension	Patch
@atlaspack/transformer-babel	Patch
@atlaspack/transformer-compiled	Patch
@atlaspack/transformer-posthtml	Patch
@atlaspack/transformer-typescript-types	Patch
@atlaspack/transformer-webextension	Patch
@atlaspack/transformer-webmanifest	Patch
@atlaspack/watcher-watchman-js	Patch
@atlaspack/validator-eslint	Patch
@atlaspack/validator-typescript	Patch
@atlaspack/resolver-default	Patch
@atlaspack/bundler-library	Patch
@atlaspack/compressor-brotli	Patch
@atlaspack/compressor-gzip	Patch
@atlaspack/compressor-raw	Patch
@atlaspack/namer-default	Patch
@atlaspack/optimizer-cssnano	Patch
@atlaspack/optimizer-htmlnano	Patch
@atlaspack/packager-raw	Patch
@atlaspack/packager-ts	Patch
@atlaspack/packager-wasm	Patch
@atlaspack/transformer-compiled-external	Patch
@atlaspack/transformer-glsl	Patch
@atlaspack/transformer-graphql	Patch
@atlaspack/transformer-inline-string	Patch
@atlaspack/transformer-inline	Patch
@atlaspack/transformer-json	Patch
@atlaspack/transformer-jsonld	Patch
@atlaspack/transformer-mdx	Patch
@atlaspack/transformer-pug	Patch
@atlaspack/transformer-raw	Patch
@atlaspack/transformer-sass	Patch
@atlaspack/transformer-svg-react	Patch
@atlaspack/transformer-svg	Patch
@atlaspack/transformer-toml	Patch
@atlaspack/transformer-typescript-tsc	Patch
@atlaspack/transformer-worklet	Patch
@atlaspack/transformer-yaml	Patch

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[marcins]

As mentioned in Slack - my main concern is that there might intentionally be a base URL without a trailing slash somewhere, but this is less likely for our internal use case (FWIW Webpack/rspack for example don't append a / - I've fallen for that before!).