In-app-uppdatering: koll mot version.json, nedladdning och installation

- CI publicerar version.json (versionCode/versionName ur APK:n, sha256,
  apkUrl) som release-asset
- Appen jämför versionCode vid start; banner på hemskärmen med
  nedladdningsprogress; sha256-verifiering; Androids installationsdialog
  via FileProvider (samma signatur -> uppdaterar rakt över)
- REQUEST_INSTALL_PACKAGES + FileProvider i manifestet

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Kf4MAbZ3c3B4Xy5XfuGsCP

.gitea/workflows/release.yaml

@@ -90,6 +90,18 @@ jobs:
           mkdir -p build
           cp app/build/outputs/apk/release/app-release.apk build/FitnessDroid.apk
           (cd build && sha256sum FitnessDroid.apk > checksums.txt && ls -la)
+          # version.json för appens inbyggda uppdateringskoll
+          VN=$("$HOME/ci-tools/build-tools/aapt2" dump badging build/FitnessDroid.apk \
+            | sed -n "s/.*versionName='\([^']*\)'.*/\1/p" | head -1)
+          SHA=$(cut -d' ' -f1 build/checksums.txt)
+          jq -n \
+            --argjson code "${{ github.run_number }}" \
+            --arg name "$VN" \
+            --arg sha "$SHA" \
+            --arg url "https://gitea.brasse-pc.eu/${{ github.repository }}/releases/download/latest/FitnessDroid.apk" \
+            '{versionCode:$code, versionName:$name, sha256:$sha, apkUrl:$url}' \
+            > build/version.json
+          cat build/version.json
 
       - name: Skapa/uppdatera latest-release + ladda upp APK
         env:
@@ -124,7 +136,7 @@ jobs:
               -d "$(jq -n --arg body "$BODY" '{body:$body}')" -o /dev/null
           fi
           echo "release id: $rid"
-          for f in FitnessDroid.apk checksums.txt; do
+          for f in FitnessDroid.apk checksums.txt version.json; do
             aid=$(curl -s "$API/repos/$REPO/releases/$rid/assets" \
               -H "Authorization: token $TOKEN" | jq -r ".[] | select(.name==\"$f\") | .id")
             if [ -n "$aid" ] && [ "$aid" != "null" ]; then