docs: update API documentation and changelog for v0.2.5 release

docs/api/client-articles/index.md

@@ -5,7 +5,9 @@ Articles related to the EchoHub TUI client built with Terminal.Gui v2.
 ## Topics
 
 - Terminal.Gui v2 patterns and conventions
-- Theme system and customization
+- Theme system and customization (including transparent theme)
 - Command system reference
-- Configuration management
+- Configuration and session persistence
+- Audio playback and file downloads
+- Automatic update checking
 - [Notification sounds](../../articles/notification-sounds.md)

docs/api/core-articles/index.md

@@ -5,5 +5,5 @@ Articles related to the EchoHub.Core shared library.
 ## Topics
 
 - Data models and DTOs
-- Contract interfaces (IChatService, IChatBroadcaster, IEchoHubClient)
+- Contract interfaces (IChatService, IChannelService, IChatBroadcaster, IEchoHubClient)
 - Validation constants and shared rules

docs/api/index.md

@@ -10,11 +10,11 @@ Terminal.Gui v2 TUI application -- UI components, services, themes, and configur
 
 ### Core
 
-Shared library -- DTOs, models, constants, and contracts (`IChatService`, `IChatBroadcaster`, `IEchoHubClient`).
+Shared library -- DTOs, models, constants, and contracts (`IChatService`, `IChannelService`, `IChatBroadcaster`, `IEchoHubClient`).
 
 ### Server
 
-ASP.NET Core server -- controllers, hubs, ChatService, SignalRBroadcaster, authentication, and data access.
+ASP.NET Core server -- controllers, hubs, ChatService, ChannelService, SignalRBroadcaster, authentication, file cleanup, and data access.
 
 ### Server.Irc
 

docs/api/server-articles/index.md

@@ -8,6 +8,7 @@ Articles related to the EchoHub server built with ASP.NET Core.
 - SignalR hub and real-time messaging
 - IRC gateway and protocol bridging
 - ChatService and broadcaster pattern
-- File upload and validation
+- ChannelService and channel CRUD
+- File upload, validation, and cleanup
 - Rate limiting configuration
-- Database schema and migrations
+- Database schema, migrations, and DataMigrationService

docs/articles/architecture.md

@@ -22,7 +22,7 @@ Shared library containing:
 
 - **Models**: `User`, `Channel`, `Message`, `RefreshToken`
 - **DTOs**: Record types for API requests/responses
-- **Contracts**: `IChatService` (protocol-agnostic chat operations), `IChatBroadcaster` (event fan-out interface), `IEchoHubClient` (SignalR client interface)
+- **Contracts**: `IChatService` (protocol-agnostic chat operations), `IChannelService` (channel CRUD and membership), `IChatBroadcaster` (event fan-out interface), `IEchoHubClient` (SignalR client interface)
 - **Constants**: `ValidationConstants` (shared regex patterns), `HubConstants`
 
 ### EchoHub.Server
@@ -33,7 +33,7 @@ ASP.NET Core web application:
 - **Hubs**: SignalR `ChatHub` -- thin adapter delegating to `IChatService`
 - **Auth**: JWT token service (15-min access tokens, 30-day refresh tokens)
 - **Data**: EF Core with SQLite
-- **Services**: `ChatService` (core business logic), `SignalRBroadcaster`, presence tracking, file storage, image-to-ASCII conversion
+- **Services**: `ChatService` (core business logic), `ChannelService` (channel CRUD and membership), `SignalRBroadcaster`, presence tracking, file storage, image-to-ASCII conversion, `FileCleanupService` (periodic removal of expired uploads), `DataMigrationService` (startup schema/data evolution)
 
 ### EchoHub.Server.Irc
 
@@ -51,9 +51,9 @@ IRC users authenticate with existing EchoHub accounts via `PASS`/`NICK`/`USER` o
 Terminal.Gui v2 TUI application:
 
 - **UI**: Main window, dialogs, chat renderer with ANSI color support
-- **Services**: API client with automatic token refresh, SignalR connection wrapper
+- **Services**: API client with automatic token refresh, SignalR connection wrapper, audio playback (NetCoreAudio), automatic update checker (AlwaysUpToDate)
-- **Themes**: 13 built-in color themes
+- **Themes**: 13 built-in color themes (including transparent theme with true terminal transparency)
-- **Config**: Client configuration management
+- **Config**: Client configuration management with session persistence ("Remember Me" refresh tokens)
 
 ## Communication
 

docs/changelog/index.md

@@ -4,7 +4,7 @@ Release history for EchoHub.
 
 ## Releases
 
-- [v0.2.5](v0.2.5.md) - Audio Playback, File Downloads & IRC Fixes
+- [v0.2.5](v0.2.5.md) - Session Persistence, Auto-Updates, Audio & Transparent Theme
 - [v0.2.4](v0.2.4.md) - E2E Message Encryption
 - [v0.2.3](v0.2.3.md) - Moderation, Embeds & UI Overhaul
 - [v0.2.2](v0.2.2.md) - Startup & Shutdown Fixes

docs/changelog/v0.2.5.md

@@ -1,4 +1,4 @@
-# v0.2.5 - Audio Playback, File Downloads & IRC Fixes
+# v0.2.5 - Session Persistence, Auto-Updates, Audio & Transparent Theme
 
 ## Features
 
@@ -12,7 +12,7 @@
 
 ### File Downloads
 
-- Press Enter on a file message in the TUI client to download it to the local machine
+- Press Enter on a file message in the TUI client to download and open it with the system default application
 - `ApiClient.DownloadFileAsync()` streams file downloads from the server
 - File and audio messages in the chat list now show colored indicators with interaction hints
 
@@ -53,6 +53,27 @@
 - New "Logout" menu item (Server menu): revokes the refresh token server-side and clears the saved session
 - Removed dead `SavedServer.Token` field (stored 15-min access token that was never read back)
 
+### Automatic Update Checking
+
+- `UpdateChecker` rewritten to use the [AlwaysUpToDate](https://github.com/AuriRex/AlwaysUpToDate) library for self-updating
+- Polls the EchoHub version manifest hourly (active only in `RELEASE` builds)
+- `UpdateConfirmDialog` shows current vs. available version with Update/Cancel buttons
+- `UpdateProgressDialog` displays real-time download progress bar
+- Errors are logged via Serilog instead of being silently swallowed
+
+### Windows Installer
+
+- New Inno Setup script (`installer/Installer.iss`) to build a Windows installer
+- Auto-reads product version from the built EXE
+- User-level install by default (no admin required), with admin override option
+- Creates desktop and quick-launch shortcuts (optional)
+- Supports English and German languages
+
+### Application Icons
+
+- New `hue_icon` branding assets (ICO, PNG, SVG) in `assets/`
+- Application icon set on both Client and Server projects
+
 ### #general Channel Protection
 
 - `#general` channel is now auto-recreated if somehow missing (both in `GetChannels` endpoint and `JoinChannel` flow)
@@ -82,6 +103,12 @@
 ## Infrastructure
 
 - Audio MIME types in `FilesController` (mp3, wav, ogg, flac, aac, m4a, wma)
+- CI workflows updated to handle Terminal.Gui submodule `nuget.config` workaround (`rm -f` step)
+- Root `nuget.config` added for package source management
+- Terminal.Gui formatting excluded from CI format checks
+- Recursive submodule fetching enabled in CI workflows
+- `Server:Admins` config array in `appsettings.example.json` for designating admin usernames
+- `Storage:CleanupIntervalHours` and `Storage:RetentionDays` added to `appsettings.example.json`
 - `FakeChannelService` test helper added for IRC unit tests
 - Test suites: ChatLine, CommandHandler, DataMigrationService, FileValidationHelper, ImageToAsciiService, IrcMessageFormatter, JwtTokenService, LinkEmbedService
 - IRC abstraction layer test suite: IrcMessage parsing, IrcMessageFormatter, IrcClientConnection, IrcCommandHandler, IrcBroadcaster