Build verified; add icon-generator tool and install/README notes

- ./gradlew assembleDebug produces a 13 MB arm64-v8a APK (libtsjet/libllama/
  libggml/libc++_shared bundled; JNI compiles cleanly against llama.cpp b10333)
- Add tools/gen_launcher_icons.py so the launcher icon is reproducible from art
- README: mark build verified, add sideload/install section

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -59,6 +59,12 @@ The APK lands in `app/build/outputs/apk/debug/`. Or just Run ▶ from Android St
 > First build compiles llama.cpp from source, so it takes a while and needs
 > network (CMake fetches the pinned llama.cpp).
 
+## Install (sideload)
+
+The debug APK is signed with the debug key, so you can sideload it directly:
+copy `app-debug.apk` to the phone, enable "install unknown apps" for your file
+manager, and tap it. First launch downloads the ~1.9 GB model over Wi-Fi.
+
 ## Where things live
 
 | What | Where |
@@ -72,12 +78,12 @@ The APK lands in `app/build/outputs/apk/debug/`. Or just Run ▶ from Android St
 
 ## TODO / notes
 
-- **Logo:** juli is on it. The header logo is a placeholder `🐟` in
-  `assets/web/index.html` (`#logo`), and there's no launcher icon yet — add an
-  `android:icon` in `AndroidManifest.xml` + a `mipmap` when the artwork is ready.
+- **Branding:** launcher icon (adaptive + legacy densities) is generated from
+  `piti-icon.png` via `python3 tools/gen_launcher_icons.py`; the header wordmark is
+  `piti-logo.png` (copied to `assets/web/logo.png`). Source art lives at the repo root.
 - The model may emit `<think>…</think>` blocks; the UI strips them from the
   display and from history (`stripThink` in `app.js`).
 - Bumping the llama.cpp tag? Re-check the C API calls in `llama-jni.cpp` against
   that tag's `include/llama.h` — it uses the raw C API directly.
-- Not yet compiled end-to-end in CI; first real build is the acid test for the
-  native layer.
+- **Build verified:** `./gradlew assembleDebug` produces a ~13 MB `arm64-v8a` APK
+  (native libs stripped; the ~1.9 GB model downloads on first launch).