Add Android control app and embedded server

Inspired by HNKServer/honoka-chan-apk-server, but implemented as a JNI-based embedded runtime instead of the original approach.

- Add an Android Compose controller app that starts and stops honoka-chan through JNI, shows runtime and health status, manages data directory mounting, and supports backup import/export for data.db
- Add an embeddable Go server entrypoint plus JNI-exported status, health, and reload hooks so desktop and Android builds share the same startup and shutdown path
- Add Android build scripts, runtime packaging, and project documentation, including generated default config.json content for honoka_runtime.zip
- Add runtime bundle hash tracking so updated honoka_runtime.zip assets are automatically redeployed while preserving config.json and user data files
- Add in-app service settings for unlock_all_special_rotation with immediate config persistence and automatic reload when the service is running
- Split SQLite driver selection by platform, using go-sqlite3 on Android and modernc.org/sqlite elsewhere to avoid Android x86_64 seccomp crashes
- Update startup, database initialization, and system health/reload handlers to support the embedded runtime and Android control flow

Signed-off-by: Sean Du <do4suki@gmail.com>

android/scripts/check_env.sh

@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+source "$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)/common.sh"
+
+ok() {
+  printf '[android] ok: %s\n' "$*"
+}
+
+warn() {
+  printf '[android] warn: %s\n' "$*" >&2
+}
+
+status=0
+
+check_cmd() {
+  local cmd="$1"
+  if command -v "$cmd" >/dev/null 2>&1; then
+    ok "command found: $cmd -> $(command -v "$cmd")"
+  else
+    warn "command missing: $cmd"
+    status=1
+  fi
+}
+
+check_file() {
+  local file="$1"
+  if [[ -f "$file" ]]; then
+    ok "file found: $file"
+  else
+    warn "file missing: $file"
+    status=1
+  fi
+}
+
+check_dir() {
+  local dir="$1"
+  if [[ -d "$dir" ]]; then
+    ok "directory found: $dir"
+  else
+    warn "directory missing: $dir"
+    status=1
+  fi
+}
+
+log "checking common commands"
+check_cmd go
+check_cmd zip
+
+SDK_ROOT="${ANDROID_SDK_ROOT:-${ANDROID_HOME:-}}"
+NDK_ROOT="${ANDROID_NDK_HOME:-${ANDROID_NDK_ROOT:-}}"
+HOST_TAG="${ANDROID_NDK_HOST_TAG:-linux-x86_64}"
+MIN_SDK="${MIN_SDK:-26}"
+
+if [[ -n "$SDK_ROOT" ]]; then
+  check_dir "$SDK_ROOT"
+else
+  warn "ANDROID_SDK_ROOT is not set"
+  status=1
+fi
+
+if [[ -n "$NDK_ROOT" ]]; then
+  check_dir "$NDK_ROOT"
+  TOOLCHAIN="$NDK_ROOT/toolchains/llvm/prebuilt/$HOST_TAG/bin"
+  check_dir "$TOOLCHAIN"
+  check_file "$TOOLCHAIN/aarch64-linux-android${MIN_SDK}-clang"
+  check_file "$TOOLCHAIN/armv7a-linux-androideabi${MIN_SDK}-clang"
+  check_file "$TOOLCHAIN/x86_64-linux-android${MIN_SDK}-clang"
+else
+  warn "ANDROID_NDK_HOME is not set"
+  status=1
+fi
+
+log "checking project files"
+check_file "$PROJECT_ROOT/assets/main.db"
+check_dir "$PROJECT_ROOT/assets/serverdata"
+check_dir "$PROJECT_ROOT/assets/certs"
+check_dir "$PROJECT_ROOT/static/templates"
+
+if [[ $status -ne 0 ]]; then
+  warn "environment check failed"
+  exit $status
+fi
+
+ok "environment check passed"