feat(example): convert to Expo app with Expo Router (#8)

* feat(example): convert to Expo app with Expo Router list→detail nav

- Remove checked-in android/ and ios/ dirs (generated by expo prebuild)
- Add expo-router with file-based routing in example/app/
- Home screen: SectionList grouping all 19 demos (Basic, Transform, Timing, Style, Loop, Advanced)
- Detail screen: dynamic route app/[demo].tsx per demo
- Extract each demo to individual files in example/src/demos/
- Demo registry in example/src/demos/index.ts for easy lookup
- Remove Gemfile (native dirs managed by expo prebuild)
- Update .gitignore to exclude generated android/ and ios/

* fix(ci): update build scripts and CI for expo prebuild

- Add build:android and build:ios scripts that run expo prebuild first
- Remove bundle install / pod install CI step (expo prebuild handles it)
- Update turbo.json inputs for generated native dirs
- Fix Gradle cache key (no longer references checked-in gradle-wrapper)

* fix(example): hide index header, remove back button title

* fix(example): use headerBackButtonDisplayMode minimal

Author: janicduplessis

.github/workflows/ci.yml

@@ -93,7 +93,7 @@ jobs:
           path: |
             ~/.gradle/wrapper
             ~/.gradle/caches
-          key: ${{ runner.os }}-gradle-${{ hashFiles('example/android/gradle/wrapper/gradle-wrapper.properties') }}
+          key: ${{ runner.os }}-gradle-${{ hashFiles('yarn.lock') }}
           restore-keys: |
             ${{ runner.os }}-gradle-
 
@@ -141,13 +141,6 @@ jobs:
         with:
           xcode-version: ${{ env.XCODE_VERSION }}
 
-      - name: Install cocoapods
-        if: env.turbo_cache_hit != 1 && steps.cocoapods-cache.outputs.cache-hit != 'true'
-        run: |
-          cd example
-          bundle install
-          bundle exec pod repo update --verbose
-          bundle exec pod install --project-directory=ios
 
       - name: Build example for iOS
         run: |

example/.gitignore

@@ -2,4 +2,8 @@
 # Expo
 .expo
 dist/
-web-build/
+web-build/
+
+# Expo prebuild generated dirs
+android/
+ios/