T0 CI workflow: unit tests with the conformance corpus.

Runs the JVM unit tests on push and pull_request with the public phyphox-docs
repository checked out next to this repository, the layout the corpus tests
expect. In CI the corpus is mandatory - a failed docs checkout fails the run;
the tests' skip-with-notice path exists for plain local clones.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: Staacks

.github/workflows/test.yml

@@ -0,0 +1,27 @@
+# T0 of the phyphox test strategy: JVM unit tests, including the conformance corpus from the
+# public phyphox-docs repository, which is checked out as a sibling of this repository - the
+# same layout the corpus lookup in app/src/test expects on a development machine. If that
+# checkout fails, the run fails: in CI the corpus is mandatory, the skip-with-notice path in
+# the tests exists for plain local clones without the sibling.
+name: tests
+on: [push, pull_request]
+jobs:
+  t0:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          path: phyphox-android
+          submodules: recursive
+      - uses: actions/checkout@v4
+        with:
+          repository: phyphox/phyphox-docs
+          path: phyphox-docs
+      - uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 21
+          cache: gradle
+      - name: Unit tests
+        run: cd phyphox-android && ./gradlew testRegularDebugUnitTest