Initial commit: HeliBoard + Gemma 4 on-device AI correction

Integrates LiteRT-LM (Google) with Gemma 4 E2B-it for on-device
spell/grammar correction in HeliBoard. After sentence-ending punctuation,
the model checks the sentence and shows a correction in the suggestion strip.
Tapping it replaces the original text — fully offline, no cloud API.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

setup_heliboard.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+# setup_heliboard.sh
+# Run once after cloning this repo to pull HeliBoard and apply AI patches.
+#
+# Model: https://huggingface.co/litert-community/gemma-4-E2B-it-litert-lm
+
+set -euo pipefail
+
+HELIBOARD_REPO="https://github.com/Helium314/HeliBoard.git"
+HELIBOARD_COMMIT="main"
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+HELIBOARD_DIR="$SCRIPT_DIR/heliboard"
+PATCHES_DIR="$SCRIPT_DIR/patches"
+
+echo "==> AIKeyboard Gemma 4 E2B Setup"
+
+if [ ! -d "$HELIBOARD_DIR/.git" ]; then
+    git clone "$HELIBOARD_REPO" "$HELIBOARD_DIR"
+fi
+
+cd "$HELIBOARD_DIR"
+git fetch origin
+git checkout "$HELIBOARD_COMMIT"
+
+echo "--> Applying Gemma 4 integration patches ..."
+for patch in "$PATCHES_DIR"/*.patch; do
+    if [ -f "$patch" ]; then
+        git apply --check "$patch" 2>/dev/null && git apply "$patch" \
+            || echo "    SKIP: $(basename "$patch") already applied or conflicts."
+    fi
+done
+
+cd "$SCRIPT_DIR"
+
+echo ""
+echo "Next steps:"
+echo "  1. Push Gemma 4 LiteRT model file to your device:"
+echo "     adb push gemma-4-E2B-it.litertlm /data/local/tmp/gemma-4-E2B-it.litertlm"
+echo "     adb shell chmod 644 /data/local/tmp/gemma-4-E2B-it.litertlm"
+echo "  2. Build & Install: ./gradlew installDebug"