chore(legacy)!: remove legacy API support and WebRTC (#1589)

## Description

Removes the legacy API, example apps, resource fetcher packages, WebRTC
package, and legacy documentation. Cleans up native bindings, build
configuration, publishing workflows, dependencies, and tests.

### Introduces a breaking change?

- [x] Yes
- [ ] No

### Type of change

- [ ] Bug fix (change which fixes an issue)
- [ ] New feature (change which adds functionality)
- [ ] Documentation update (improves or adds clarity to existing
documentation)
- [x] Other (chores, tests, code style improvements etc.)

### Tested on

- [ ] iOS
- [ ] Android

### Testing instructions

- [x] Clean-build the computer vision, NLP, and speech example apps on
Android and iOS.
- [x] Launch each app and confirm native initialization succeeds.
- [ ] Confirm archived versioned documentation is correct.

### Screenshots

<!-- Add screenshots here, if applicable -->

### Related issues

Closes #1421 

### Checklist

- [ ] I have performed a self-review of my code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have updated the documentation accordingly
- [ ] My changes generate no new warnings

### Additional notes

<!-- Include any additional information, assumptions, or context that
reviewers might need to understand this PR. -->

Author: barhanc

.eslintrc.js

@@ -73,21 +73,6 @@ module.exports = {
         'no-console': 'warn',
       },
     },
-    {
-      // ==============================================================================
-      // LEGACY SUPPORT: disable v0.10 lint rules for legacy code (remove when legacy is dropped)
-      // ==============================================================================
-      files: [
-        'packages/react-native-executorch/legacy/**/*.{js,jsx,ts,tsx}',
-        'packages/bare-resource-fetcher/**/*.{js,jsx,ts,tsx}',
-        'packages/expo-resource-fetcher/**/*.{js,jsx,ts,tsx}',
-      ],
-      rules: {
-        'jsdoc/match-description': 'off',
-        'camelcase': 'off',
-        'eslint-comments/no-unused-disable': 'off',
-      },
-    },
     {
       // The JSDoc rules exist to keep the generated API reference complete.
       // Test helpers are not part of that surface, and requiring a tag per

.gitattributes

@@ -2,11 +2,10 @@
 # specific for windows script files
 *.bat text eol=crlf
 
-# Exclude apps, third-party, and legacy code from language stats & line counts
+# Exclude apps and third-party code from language stats & line counts
 apps/** linguist-vendored
 third-party/** linguist-vendored
 **/third-party/** linguist-vendored
-**/legacy/** linguist-vendored
 
 # Exclude documentation from codebase language stats
 docs/** linguist-documentation

.github/workflows/ci.yml

@@ -70,11 +70,11 @@ jobs:
 
           # eslint, tsc and jest read none of the C++ trees, and none of the
           # documentation.
-          ts_irrelevant='^(docs/|[^/]+\.md$|packages/react-native-executorch/(cpp|legacy/cpp)/)'
+          ts_irrelevant='^(docs/|[^/]+\.md$|packages/react-native-executorch/cpp/)'
           if echo "$files" | grep -qvE "$ts_irrelevant"; then ts=true; else ts=false; fi
 
           # The C++ suite compiles cpp/ only (cpp/tests/CMakeLists.txt globs
-          # core/ and extensions/, never legacy/). The rest of this list is what
+          # core/ and extensions/). The rest of this list is what
           # decides which ExecuTorch release it builds and links against:
           # package.json carries nativeLibsVersion, which download-libs.js reads
           # to pick the headers release, and the CI job cross-checks that
@@ -147,7 +147,7 @@ jobs:
         run: yarn lint
 
       - name: Typecheck files
-        run: yarn workspaces foreach --all --exclude react-native-executorch-webrtc --topological-dev run prepare && yarn typecheck
+        run: yarn workspaces foreach --all --topological-dev run prepare && yarn typecheck
 
   build-library:
     needs: changes
@@ -161,7 +161,7 @@ jobs:
         uses: ./.github/actions/setup
 
       - name: Build all packages
-        run: yarn workspaces foreach --all --exclude react-native-executorch-webrtc --topological-dev run prepare
+        run: yarn workspaces foreach --all --topological-dev run prepare
 
   native-tests:
     name: C++ unit tests

.github/workflows/npm-publish-satellites.yml

@@ -78,7 +78,7 @@ jobs:
         if: ${{ env.EXECUTORCH_VERSION == 'PLACEHOLDER' }}
         run: exit 1 # this should never happen
 
-      # The root workspaces glob is packages/* + apps/* + apps/legacy/*, so a
+      # The root workspaces glob is packages/* + apps/*, so a
       # plain `yarn install` pulled 1659 packages (597 MiB) to build one of
       # them: 164s of a 197s job, against 19s for the actual build. `workspaces
       # focus` installs only this package's tree; it is built into Yarn 4, the

.github/workflows/npm-publish.yml

@@ -92,11 +92,6 @@ ios/generated
 android/generated
 apps/*/ios/
 apps/*/android/
-# === LEGACY SUPPORT: Expo prebuild directories for legacy apps (remove when legacy apps are dropped) ===
-apps/legacy/*/ios/
-apps/legacy/*/android/
-!apps/legacy/bare-rn/ios/
-!apps/legacy/bare-rn/android/
 **/Pods/
 
 # generated TypeDoc API reference (regenerated at build time)