Refactor API integration and enhance command handling

- Removed unused modules and updated module paths for clarity.
- Added autocomplete functionality for command input in InputState.
- Updated AppStateRest to include a method for checking if a turn is in flight.
- Refactored subagent engine to use new API client structure.
- Changed default provider from "openrouter" to "zen" with updated API keys and models.
- Implemented tests for memory management and edit log functionalities.
- Enhanced error handling in API requests and improved response parsing.
- Updated UI components to reflect new API provider and status indicators.

src/app/mode/onboard_provider.rs

@@ -1,13 +1,12 @@
 use crate::model::settings::Settings;
 
-pub const PROVIDERS: &[&str] = &["OpenRouter", "Anthropic", "OpenAI"];
+pub const PROVIDERS: &[&str] = &["Zen API", "OpenAI"];
 
 pub fn set_provider(settings: &mut Settings, provider: &str) {
     settings.provider = match provider {
-        "OpenRouter" => "openrouter".to_string(),
-        "Anthropic" => "anthropic".to_string(),
+        "Zen API" => "zen".to_string(),
         "OpenAI" => "openai".to_string(),
-        _ => "openrouter".to_string(),
+        _ => "zen".to_string(),
     };
 }