add context window monitor

Writes the current context window to logs/current_context_window (uses a symlink to a session ID).

This PR was unfortunately generated by a different LLM and did a ton of superficial reformating, it's actually a fairly small and benign change, but I don't want to roll back everything. Hope that's ok.

crates/g3-config/src/tests.rs

@@ -9,7 +9,7 @@ mod tests {
         // Create a temporary directory for the test config
         let temp_dir = TempDir::new().unwrap();
         let config_path = temp_dir.path().join("test_config.toml");
-        
+
         // Write a test configuration with coach and player providers
         let config_content = r#"
 [providers]
@@ -35,32 +35,32 @@ fallback_default_max_tokens = 8192
 enable_streaming = true
 timeout_seconds = 60
 "#;
-        
+
         fs::write(&config_path, config_content).unwrap();
-        
+
         // Load the configuration
         let config = Config::load(Some(config_path.to_str().unwrap())).unwrap();
-        
+
         // Test that the providers are correctly identified
         assert_eq!(config.providers.default_provider, "databricks");
         assert_eq!(config.get_coach_provider(), "anthropic");
         assert_eq!(config.get_player_provider(), "embedded");
-        
+
         // Test creating coach config
         let coach_config = config.for_coach().unwrap();
         assert_eq!(coach_config.providers.default_provider, "anthropic");
-        
+
         // Test creating player config
         let player_config = config.for_player().unwrap();
         assert_eq!(player_config.providers.default_provider, "embedded");
     }
-    
+
     #[test]
     fn test_coach_player_fallback_to_default() {
         // Create a temporary directory for the test config
         let temp_dir = TempDir::new().unwrap();
         let config_path = temp_dir.path().join("test_config.toml");
-        
+
         // Write a test configuration WITHOUT coach and player providers
         let config_content = r#"
 [providers]
@@ -76,31 +76,31 @@ fallback_default_max_tokens = 8192
 enable_streaming = true
 timeout_seconds = 60
 "#;
-        
+
         fs::write(&config_path, config_content).unwrap();
-        
+
         // Load the configuration
         let config = Config::load(Some(config_path.to_str().unwrap())).unwrap();
-        
+
         // Test that coach and player fall back to default provider
         assert_eq!(config.get_coach_provider(), "databricks");
         assert_eq!(config.get_player_provider(), "databricks");
-        
+
         // Test creating coach config (should use default)
         let coach_config = config.for_coach().unwrap();
         assert_eq!(coach_config.providers.default_provider, "databricks");
-        
+
         // Test creating player config (should use default)
         let player_config = config.for_player().unwrap();
         assert_eq!(player_config.providers.default_provider, "databricks");
     }
-    
+
     #[test]
     fn test_invalid_provider_error() {
         // Create a temporary directory for the test config
         let temp_dir = TempDir::new().unwrap();
         let config_path = temp_dir.path().join("test_config.toml");
-        
+
         // Write a test configuration with an unconfigured provider
         let config_content = r#"
 [providers]
@@ -117,15 +117,15 @@ fallback_default_max_tokens = 8192
 enable_streaming = true
 timeout_seconds = 60
 "#;
-        
+
         fs::write(&config_path, config_content).unwrap();
-        
+
         // Load the configuration
         let config = Config::load(Some(config_path.to_str().unwrap())).unwrap();
-        
+
         // Test that trying to create a coach config with unconfigured provider fails
         let result = config.for_coach();
         assert!(result.is_err());
         assert!(result.unwrap_err().to_string().contains("not configured"));
     }
-}
+}