add code exploration fast start

This tries to short-circuit multiple round-trips to llm for reading code.
It's a precursor to trying to context engineer tailored to specific tasks.
In initial experiments, it's only marginally faster than regular mode, and burns more tokens.

crates/g3-providers/src/anthropic.rs

@@ -678,6 +678,14 @@ impl LLMProvider for AnthropicProvider {
         // Anthropic supports cache control
         true
     }
+    
+    fn max_tokens(&self) -> u32 {
+        self.max_tokens
+    }
+    
+    fn temperature(&self) -> f32 {
+        self.temperature
+    }
 }
 
 // Anthropic API request/response structures

crates/g3-providers/src/databricks.rs

@@ -1055,6 +1055,14 @@ impl LLMProvider for DatabricksProvider {
     fn supports_cache_control(&self) -> bool {
         false
     }
+    
+    fn max_tokens(&self) -> u32 {
+        self.max_tokens
+    }
+    
+    fn temperature(&self) -> f32 {
+        self.temperature
+    }
 }
 
 // Databricks API request/response structures

crates/g3-providers/src/embedded.rs

@@ -771,4 +771,12 @@ impl LLMProvider for EmbeddedProvider {
     fn model(&self) -> &str {
         &self.model_name
     }
+    
+    fn max_tokens(&self) -> u32 {
+        self.max_tokens
+    }
+    
+    fn temperature(&self) -> f32 {
+        self.temperature
+    }
 }

crates/g3-providers/src/lib.rs

@@ -26,6 +26,12 @@ pub trait LLMProvider: Send + Sync {
     fn supports_cache_control(&self) -> bool {
         false
     }
+    
+    /// Get the configured max_tokens for this provider
+    fn max_tokens(&self) -> u32;
+    
+    /// Get the configured temperature for this provider
+    fn temperature(&self) -> f32;
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]

crates/g3-providers/src/openai.rs

@@ -384,6 +384,14 @@ impl LLMProvider for OpenAIProvider {
         // OpenAI models support native tool calling
         true
     }
+    
+    fn max_tokens(&self) -> u32 {
+        self.max_tokens.unwrap_or(16000)
+    }
+    
+    fn temperature(&self) -> f32 {
+        self._temperature.unwrap_or(0.1)
+    }
 }
 
 fn convert_messages(messages: &[Message]) -> Vec<serde_json::Value> {