add google photos support & fix preview

shared/client/src/main/java/dev/photosync/client/PhotoSyncClient.java

@@ -53,9 +53,15 @@ public final class PhotoSyncClient implements AutoCloseable {
     private final AutoCapture autoCapture;
 
     public PhotoSyncClient(ClientBridge bridge) {
-        this(bridge, new PhotoSync(new ConfigLocations(
-                bridge.game().configDirectory(),
-                bridge.game().userDataDirectory())), Theme.dark());
+        this(bridge, new PhotoSync(
+                new ConfigLocations(
+                        bridge.game().configDirectory(),
+                        bridge.game().userDataDirectory()),
+                // How Google Photos gets the player in front of its consent
+                // page. Core cannot open a browser, and the sign-in is called
+                // from a worker, so this hops back to the render thread the way
+                // everything else that touches the game does.
+                url -> bridge.game().submit(() -> bridge.game().openUrl(url))), Theme.dark());
     }
 
     /** Takes its collaborators explicitly so a test can drive it without a game. */

shared/client/src/main/resources/assets/photosync/lang/en_us.json

@@ -126,5 +126,10 @@
   "photosync.provider.immich.endpoint": "Server URL",
   "photosync.provider.immich.endpoint.hint": "https://photos.example.com",
   "photosync.provider.immich.secret": "API key",
-  "photosync.provider.immich.secret.hint": "Account settings -> API Keys"
+  "photosync.provider.immich.secret.hint": "Account settings -> API Keys",
+  "photosync.provider.googlephotos.name": "Google Photos",
+  "photosync.provider.googlephotos.endpoint": "OAuth client ID",
+  "photosync.provider.googlephotos.endpoint.hint": "Google Cloud -> Credentials -> Desktop app",
+  "photosync.provider.googlephotos.secret": "OAuth client secret",
+  "photosync.provider.googlephotos.secret.hint": "From the same client; Test connection signs you in"
 }

shared/client/src/main/resources/assets/photosync/lang/zh_cn.json

@@ -126,5 +126,10 @@
   "photosync.provider.immich.endpoint": "服务器地址",
   "photosync.provider.immich.endpoint.hint": "https://photos.example.com",
   "photosync.provider.immich.secret": "API 密钥",
-  "photosync.provider.immich.secret.hint": "账户设置 -> API 密钥"
+  "photosync.provider.immich.secret.hint": "账户设置 -> API 密钥",
+  "photosync.provider.googlephotos.name": "Google 相册",
+  "photosync.provider.googlephotos.endpoint": "OAuth 客户端 ID",
+  "photosync.provider.googlephotos.endpoint.hint": "Google Cloud -> 凭据 -> 桌面应用",
+  "photosync.provider.googlephotos.secret": "OAuth 客户端密钥",
+  "photosync.provider.googlephotos.secret.hint": "同一客户端；点击“测试连接”完成登录"
 }