Add in-game settings menu with web panel sync

Features:
- SettingsActivity accessible via Menu button (keycode 82)
- Configure server URL and mode (online/offline) in-game
- Test connection before saving settings
- Switch to offline mode with one tap
- Sync settings from web admin panel
- Real-time status messages with emoji indicators

Implementation:
- Created 13 SettingsActivity Smali files (main + inner classes)
- Created activity_settings.xml UI layout
- Added SettingsActivity to AndroidManifest.xml (portrait mode)
- Modified MainActivity.smali to handle Menu button press
- Integrated with existing ServerManager for Nimble SDK overrides
- Settings stored in SharedPreferences (rr3_server_config.xml)

APK:
- Built and signed: RR3-v14-Settings-Menu.apk (103 MB)
- Keystore: rr3-release.keystore (alias: rr3key)
- Ready for distribution

Related server changes:
- ServerSettingsController.cs with 3 API endpoints
- DeviceSettings.cshtml admin page
- UserSettings database model and migration

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

smali_classes2/com/firemint/realracing/SettingsActivity$2.smali

@@ -0,0 +1,72 @@
+.class Lcom/firemint/realracing/SettingsActivity$2;
+.super Ljava/lang/Object;
+.source "SettingsActivity.java"
+
+# interfaces
+.implements Landroid/view/View$OnClickListener;
+
+# annotations
+.annotation system Ldalvik/annotation/EnclosingMethod;
+    value = Lcom/firemint/realracing/SettingsActivity;->onCreate(Landroid/os/Bundle;)V
+.end annotation
+
+.annotation system Ldalvik/annotation/InnerClass;
+    accessFlags = 0x0
+    name = null
+.end annotation
+
+# instance fields
+.field final synthetic this$0:Lcom/firemint/realracing/SettingsActivity;
+
+# direct methods
+.method constructor <init>(Lcom/firemint/realracing/SettingsActivity;)V
+    .registers 2
+    .param p1, "this$0"    # Lcom/firemint/realracing/SettingsActivity;
+
+    .line 145
+    iput-object p1, p0, Lcom/firemint/realracing/SettingsActivity$2;->this$0:Lcom/firemint/realracing/SettingsActivity;
+
+    invoke-direct {p0}, Ljava/lang/Object;-><init>()V
+
+    return-void
+.end method
+
+# virtual methods
+.method public onClick(Landroid/view/View;)V
+    .registers 4
+    .param p1, "v"    # Landroid/view/View;
+
+    .line 148
+    iget-object v0, p0, Lcom/firemint/realracing/SettingsActivity$2;->this$0:Lcom/firemint/realracing/SettingsActivity;
+
+    const v1, 0x7f0a047b
+
+    invoke-virtual {v0, v1}, Lcom/firemint/realracing/SettingsActivity;->findViewById(I)Landroid/view/View;
+
+    move-result-object v0
+
+    check-cast v0, Landroid/widget/EditText;
+
+    .line 149
+    .local v0, "etServerUrl":Landroid/widget/EditText;
+    invoke-virtual {v0}, Landroid/widget/EditText;->getText()Landroid/text/Editable;
+
+    move-result-object v1
+
+    invoke-virtual {v1}, Ljava/lang/Object;->toString()Ljava/lang/String;
+
+    move-result-object v1
+
+    invoke-virtual {v1}, Ljava/lang/String;->trim()Ljava/lang/String;
+
+    move-result-object v1
+
+    .line 151
+    .local v1, "url":Ljava/lang/String;
+    iget-object v0, p0, Lcom/firemint/realracing/SettingsActivity$2;->this$0:Lcom/firemint/realracing/SettingsActivity;
+
+    invoke-virtual {v0, v1}, Lcom/firemint/realracing/SettingsActivity;->testConnection(Ljava/lang/String;)V
+
+    .line 152
+    return-void
+.end method