feat: add temperature and max_tokens support for Custom REST providers (v0.2.9)

- Added max_tokens and temperature fields to ProviderConfig
- Custom REST providers now send modelConfig with temperature and max_tokens
- OpenAI-compatible providers now use configured max_tokens/temperature
- Both formats fall back to defaults if not specified
- Bumped version to 0.2.9

This allows users to configure response length and randomness for all
AI providers, including Custom REST providers which require modelConfig format.

src-tauri/src/ai/openai.rs

@@ -56,12 +56,19 @@ impl OpenAiProvider {
             .unwrap_or("/chat/completions");
         let url = format!("{}{}", config.api_url.trim_end_matches('/'), endpoint_path);
 
-        let body = serde_json::json!({
+        let mut body = serde_json::json!({
             "model": config.model,
             "messages": messages,
-            "max_tokens": 4096,
         });
 
+        // Add max_tokens if provided, otherwise use default 4096
+        body["max_tokens"] = serde_json::Value::from(config.max_tokens.unwrap_or(4096));
+
+        // Add temperature if provided
+        if let Some(temp) = config.temperature {
+            body["temperature"] = serde_json::Value::from(temp);
+        }
+
         // Use custom auth header and prefix if provided
         let auth_header = config.custom_auth_header.as_deref().unwrap_or("Authorization");
         let auth_prefix = config.custom_auth_prefix.as_deref().unwrap_or("Bearer ");
@@ -149,6 +156,18 @@ impl OpenAiProvider {
             body["sessionId"] = serde_json::Value::String(session_id.clone());
         }
 
+        // Add modelConfig with temperature and max_tokens if provided
+        let mut model_config = serde_json::json!({});
+        if let Some(temp) = config.temperature {
+            model_config["temperature"] = serde_json::Value::from(temp);
+        }
+        if let Some(max_tokens) = config.max_tokens {
+            model_config["max_tokens"] = serde_json::Value::from(max_tokens);
+        }
+        if !model_config.is_null() && model_config.as_object().map_or(false, |obj| !obj.is_empty()) {
+            body["modelConfig"] = model_config;
+        }
+
         // Use custom auth header and prefix (no prefix for MSI GenAI)
         let auth_header = config
             .custom_auth_header

src-tauri/src/state.rs

@@ -10,6 +10,12 @@ pub struct ProviderConfig {
     pub api_url: String,
     pub api_key: String,
     pub model: String,
+    /// Optional: Maximum tokens for response
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub max_tokens: Option<u32>,
+    /// Optional: Temperature (0.0-2.0) - controls randomness
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub temperature: Option<f64>,
     /// Optional: Custom endpoint path (e.g., "" for no path, "/v1/chat" for custom path)
     /// If None, defaults to "/chat/completions" for OpenAI compatibility
     #[serde(skip_serializing_if = "Option::is_none")]

src-tauri/tauri.conf.json

@@ -1,6 +1,6 @@
 {
   "productName": "TFTSR",
-  "version": "0.2.8",
+  "version": "0.2.9",
   "identifier": "com.tftsr.devops",
   "build": {
     "frontendDist": "../dist",