Feature: Audio Device Selection

[Tiberius-Sicae]

Pull Request: Audio Device Selection for Text-to-Speech & Audio Output

Summary

This PR adds the ability for users to select a specific audio playback device for all speech and audio generated by EDDI, rather than always outputting to the default Windows audio device.

The selected device configuration persists across sessions. If the configured device becomes unavailable (e.g., unplugged), the app automatically and gracefully falls back to the system's "Default Device" and saves that update.

Additionally, this PR features a zero-overhead window message listener to automatically refresh available audio devices and update selection when hardware is plugged in or unplugged in real-time.

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Detailed Changes

1. Configuration Storage & Logic

• ConfigService/Configurations/SpeechServiceConfiguration.cs:
  • Added AudioDevice property (serialised as audioDevice in speech.json) to persist the chosen device ID.
  • Reset AudioDevice to null on Clear().

2. Audio Device Enumeration & Playback Routing

• SpeechService/AudioDevice.cs:
  • Added AudioDevice representation class.
  • Created AudioDeviceService with a static method GetAudioDevices() to query active audio endpoints using NAudio.
• SpeechService/SoundManager.cs:
  • Updated GetSoundOut(IWaveProvider provider) to check speechServiceConfiguration.AudioDevice.
  • If a specific device ID is configured, resolves it to an MMDevice and instantiates WasapiOut(device, ...).
  • Implemented robust exception handling to fall back to the default new WasapiOut() if the device is not found or fails to initialise.

3. User Interface, Localisation & Real-time Tracking

• EddiUI/Properties/Resources.resx & Resources.Designer.cs:
  • Added localised label tab_tts_audio_device_label ("Audio device:").
• EddiUI/TextToSpeechTab.xaml:
  • Added a row to the grid layout and inserted the "Audio device" dropdown combobox above the "Voice" dropdown.
• EddiUI/TextToSpeechTab.xaml.cs:
  • Populates the audio device combobox with available devices plus a "Default Device" placeholder.
  • Checks if the configured device is available in the options. If missing/unplugged, sets selection to "Default Device" and clears the configured ID permanently.
  • Registered a WM_DEVICECHANGE (0x0219) native message hook on Loaded (removed on Unloaded) to catch system hardware changes. This allows the dropdown list and selection to refresh dynamically in real-time without background polling overhead.

4. Build System Fix

• BuildInstaller/BuildInstaller.csproj:
  • Wrapped the $(SolutionDir) path in double-quotes inside the PostBuildEvent batch command invocation. This fixes a build failure that occurred when the project was located in a path containing spaces.

[Tkael]

This works equally well for both speech and audio clips. I'll convert the hardcoded "Default Device" string into a localizable resource and then merge. o7