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>

internal/schema/system/system.go

@@ -0,0 +1,21 @@
+package systemschema
+
+type HealthResp struct {
+	Status                string `json:"status"`
+	AppName               string `json:"app_name"`
+	Version               string `json:"version"`
+	StartedAt             string `json:"started_at"`
+	UptimeSeconds         int64  `json:"uptime_seconds"`
+	LastReloadAt          string `json:"last_reload_at,omitempty"`
+	ListenPort            string `json:"listen_port"`
+	CdnServer             string `json:"cdn_server"`
+	ReloadTokenConfigured bool   `json:"reload_token_configured"`
+	MainDB                string `json:"main_db"`
+	UserDB                string `json:"user_db"`
+}
+
+type ReloadResp struct {
+	Status     string `json:"status"`
+	Message    string `json:"message"`
+	ReloadedAt string `json:"reloaded_at,omitempty"`
+}