Add Phase 1 critical endpoints: Config & Save/Load system

- Added ConfigController with 4 endpoints:
  - getGameConfig: Server config, feature flags, URLs
  - getServerTime: UTC timestamps
  - getFeatureFlags: Feature toggles
  - getServerStatus: Health check

- Added save/load system to ProgressionController:
  - POST /save/{synergyId}: Save JSON blob
  - GET /save/{synergyId}/load: Load JSON blob
  - Version tracking and timestamps

- Added PlayerSave entity to database:
  - Stores arbitrary JSON game state
  - Version tracking (increments on save)
  - LastModified timestamps

- Updated appsettings.json:
  - ServerSettings section (version, URLs, MOTD)
  - FeatureFlags section (7 feature toggles)

- Created migration: AddPlayerSavesAndConfig
- Updated ApiModels with new DTOs
- All endpoints tested and working

Phase 1 objectives complete:
✅ Synergy ID generation (already existed)
✅ Configuration endpoints (new)
✅ Save/load system (new)

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

RR3CommunityServer/Controllers/ConfigController.cs

@@ -0,0 +1,143 @@
+using Microsoft.AspNetCore.Mvc;
+using RR3CommunityServer.Models;
+
+namespace RR3CommunityServer.Controllers;
+
+[ApiController]
+[Route("config/api/android")]
+public class ConfigController : ControllerBase
+{
+    private readonly IConfiguration _configuration;
+    private readonly ILogger<ConfigController> _logger;
+
+    public ConfigController(IConfiguration configuration, ILogger<ConfigController> logger)
+    {
+        _configuration = configuration;
+        _logger = logger;
+    }
+
+    /// <summary>
+    /// Get game configuration - server time, feature flags, version info
+    /// </summary>
+    [HttpGet("getGameConfig")]
+    public ActionResult<SynergyResponse<GameConfig>> GetGameConfig()
+    {
+        _logger.LogInformation("GetGameConfig request");
+
+        var config = new GameConfig
+        {
+            ServerTime = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+            ServerVersion = _configuration["ServerSettings:Version"] ?? "1.0.0",
+            GameVersion = _configuration["ServerSettings:GameVersion"] ?? "14.0.1",
+            MaintenanceMode = bool.Parse(_configuration["ServerSettings:MaintenanceMode"] ?? "false"),
+            MessageOfTheDay = _configuration["ServerSettings:MessageOfTheDay"] ?? "Welcome to RR3 Community Server!",
+            FeatureFlags = new FeatureFlags
+            {
+                MultiplayerEnabled = bool.Parse(_configuration["FeatureFlags:MultiplayerEnabled"] ?? "false"),
+                LeaderboardsEnabled = bool.Parse(_configuration["FeatureFlags:LeaderboardsEnabled"] ?? "true"),
+                DailyRewardsEnabled = bool.Parse(_configuration["FeatureFlags:DailyRewardsEnabled"] ?? "true"),
+                TimeTrialsEnabled = bool.Parse(_configuration["FeatureFlags:TimeTrialsEnabled"] ?? "true"),
+                CustomContentEnabled = bool.Parse(_configuration["FeatureFlags:CustomContentEnabled"] ?? "true"),
+                SpecialEventsEnabled = bool.Parse(_configuration["FeatureFlags:SpecialEventsEnabled"] ?? "true"),
+                AllItemsFree = bool.Parse(_configuration["FeatureFlags:AllItemsFree"] ?? "true")
+            },
+            Urls = new ServerUrls
+            {
+                BaseUrl = _configuration["ServerSettings:BaseUrl"] ?? "http://localhost:5001",
+                AssetsUrl = _configuration["ServerSettings:AssetsUrl"] ?? "http://localhost:5001/content/api",
+                LeaderboardsUrl = _configuration["ServerSettings:LeaderboardsUrl"] ?? "http://localhost:5001/leaderboards/api",
+                MultiplayerUrl = _configuration["ServerSettings:MultiplayerUrl"] ?? "http://localhost:5001/multiplayer/api"
+            }
+        };
+
+        var response = new SynergyResponse<GameConfig>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = config
+        };
+
+        return Ok(response);
+    }
+
+    /// <summary>
+    /// Get server time (Unix timestamp)
+    /// </summary>
+    [HttpGet("getServerTime")]
+    public ActionResult<SynergyResponse<ServerTime>> GetServerTime()
+    {
+        _logger.LogInformation("GetServerTime request");
+
+        var response = new SynergyResponse<ServerTime>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = new ServerTime
+            {
+                ServerTimestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds(),
+                ServerTimeMs = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(),
+                Timezone = "UTC",
+                IsDST = false
+            }
+        };
+
+        return Ok(response);
+    }
+
+    /// <summary>
+    /// Get feature flags
+    /// </summary>
+    [HttpGet("getFeatureFlags")]
+    public ActionResult<SynergyResponse<FeatureFlags>> GetFeatureFlags()
+    {
+        _logger.LogInformation("GetFeatureFlags request");
+
+        var flags = new FeatureFlags
+        {
+            MultiplayerEnabled = bool.Parse(_configuration["FeatureFlags:MultiplayerEnabled"] ?? "false"),
+            LeaderboardsEnabled = bool.Parse(_configuration["FeatureFlags:LeaderboardsEnabled"] ?? "true"),
+            DailyRewardsEnabled = bool.Parse(_configuration["FeatureFlags:DailyRewardsEnabled"] ?? "true"),
+            TimeTrialsEnabled = bool.Parse(_configuration["FeatureFlags:TimeTrialsEnabled"] ?? "true"),
+            CustomContentEnabled = bool.Parse(_configuration["FeatureFlags:CustomContentEnabled"] ?? "true"),
+            SpecialEventsEnabled = bool.Parse(_configuration["FeatureFlags:SpecialEventsEnabled"] ?? "true"),
+            AllItemsFree = bool.Parse(_configuration["FeatureFlags:AllItemsFree"] ?? "true")
+        };
+
+        var response = new SynergyResponse<FeatureFlags>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = flags
+        };
+
+        return Ok(response);
+    }
+
+    /// <summary>
+    /// Check server status and health
+    /// </summary>
+    [HttpGet("getServerStatus")]
+    public ActionResult<SynergyResponse<ServerStatus>> GetServerStatus()
+    {
+        _logger.LogInformation("GetServerStatus request");
+
+        var status = new ServerStatus
+        {
+            Status = "online",
+            Version = _configuration["ServerSettings:Version"] ?? "1.0.0",
+            MaintenanceMode = bool.Parse(_configuration["ServerSettings:MaintenanceMode"] ?? "false"),
+            PlayerCount = 0, // TODO: Implement player counting
+            Uptime = Environment.TickCount64 / 1000, // Seconds since server start
+            Message = _configuration["ServerSettings:MessageOfTheDay"] ?? string.Empty
+        };
+
+        var response = new SynergyResponse<ServerStatus>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = status
+        };
+
+        return Ok(response);
+    }
+}