fix: resolve all compilation errors and clippy warnings

This commit fixes 12 categories of errors across the codebase:

- Fix owlen-mcp-llm-server build target conflict by renaming lib.rs to main.rs
- Resolve ambiguous glob re-exports in owlen-core by using explicit exports
- Add Default derive to MockMcpClient and MockProvider test utilities
- Remove unused imports from owlen-core test files
- Fix needless borrows in test file arguments
- Improve Config initialization style in mode_tool_filter tests
- Make AgentExecutor::parse_response public for testing
- Remove non-existent max_tool_calls field from AgentConfig usage
- Fix AgentExecutor::new calls to use correct 3-argument signature
- Fix AgentResult field access in agent tests
- Use Debug formatting instead of Display for AgentResult
- Remove unnecessary default() calls on unit structs

All changes ensure the project compiles cleanly with:
- cargo check --all-targets ✓
- cargo clippy --all-targets -- -D warnings ✓
- cargo test --no-run ✓

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

crates/owlen-cli/tests/agent_tests.rs

@@ -82,10 +82,9 @@ async fn test_agent_single_tool_scenario() {
         model: "llama3.2".to_string(),
         temperature: Some(0.7),
         max_tokens: None,
-        max_tool_calls: 10,
     };
 
-    let executor = AgentExecutor::new(provider, mcp_client, config, None);
+    let executor = AgentExecutor::new(provider, mcp_client, config);
 
     // Simple query that should complete in one tool call
     let result = executor
@@ -93,9 +92,12 @@ async fn test_agent_single_tool_scenario() {
         .await;
 
     match result {
-        Ok(answer) => {
-            assert!(!answer.is_empty(), "Answer should not be empty");
-            println!("Agent answer: {}", answer);
+        Ok(agent_result) => {
+            assert!(
+                !agent_result.answer.is_empty(),
+                "Answer should not be empty"
+            );
+            println!("Agent answer: {}", agent_result.answer);
         }
         Err(e) => {
             // It's okay if this fails due to LLM not following format
@@ -116,10 +118,9 @@ async fn test_agent_multi_step_workflow() {
         model: "llama3.2".to_string(),
         temperature: Some(0.5), // Lower temperature for more consistent behavior
         max_tokens: None,
-        max_tool_calls: 20,
     };
 
-    let executor = AgentExecutor::new(provider, mcp_client, config, None);
+    let executor = AgentExecutor::new(provider, mcp_client, config);
 
     // Query requiring multiple steps: list -> read -> analyze
     let result = executor
@@ -127,9 +128,9 @@ async fn test_agent_multi_step_workflow() {
         .await;
 
     match result {
-        Ok(answer) => {
-            assert!(!answer.is_empty());
-            println!("Multi-step answer: {}", answer);
+        Ok(agent_result) => {
+            assert!(!agent_result.answer.is_empty());
+            println!("Multi-step answer: {:?}", agent_result);
         }
         Err(e) => {
             println!("Multi-step test skipped: {}", e);
@@ -148,10 +149,9 @@ async fn test_agent_iteration_limit() {
         model: "llama3.2".to_string(),
         temperature: Some(0.7),
         max_tokens: None,
-        max_tool_calls: 5,
     };
 
-    let executor = AgentExecutor::new(provider, mcp_client, config, None);
+    let executor = AgentExecutor::new(provider, mcp_client, config);
 
     // Complex query that would require many iterations
     let result = executor
@@ -186,14 +186,13 @@ async fn test_agent_tool_budget_enforcement() {
     let mcp_client = Arc::clone(&provider) as Arc<RemoteMcpClient>;
 
     let config = AgentConfig {
-        max_iterations: 20,
+        max_iterations: 3, // Very low iteration limit to enforce budget
         model: "llama3.2".to_string(),
         temperature: Some(0.7),
         max_tokens: None,
-        max_tool_calls: 3, // Very low tool call budget
     };
 
-    let executor = AgentExecutor::new(provider, mcp_client, config, None);
+    let executor = AgentExecutor::new(provider, mcp_client, config);
 
     // Query that would require many tool calls
     let result = executor
@@ -238,7 +237,7 @@ fn create_test_executor() -> AgentExecutor {
     let mcp_client = Arc::clone(&provider) as Arc<RemoteMcpClient>;
 
     let config = AgentConfig::default();
-    AgentExecutor::new(provider, mcp_client, config, None)
+    AgentExecutor::new(provider, mcp_client, config)
 }
 
 #[test]
@@ -248,7 +247,7 @@ fn test_agent_config_defaults() {
     assert_eq!(config.max_iterations, 10);
     assert_eq!(config.model, "ollama");
     assert_eq!(config.temperature, Some(0.7));
-    assert_eq!(config.max_tool_calls, 20);
+    // max_tool_calls field removed - agent now tracks iterations instead
 }
 
 #[test]
@@ -258,12 +257,10 @@ fn test_agent_config_custom() {
         model: "custom-model".to_string(),
         temperature: Some(0.5),
         max_tokens: Some(2000),
-        max_tool_calls: 30,
     };
 
     assert_eq!(config.max_iterations, 15);
     assert_eq!(config.model, "custom-model");
     assert_eq!(config.temperature, Some(0.5));
     assert_eq!(config.max_tokens, Some(2000));
-    assert_eq!(config.max_tool_calls, 30);
 }