Fix mismatching backend agent orderings

Author: CSRessel

src/app.rs

@@ -2,7 +2,6 @@
 
 use crate::backends;
 use crate::backends::AgentBackend;
-use crate::backends::claude::ClaudeBackend;
 use crate::conversation::ConversationEvent;
 use crate::history::{
     CommittedInlineEntry, InlineEntryId, InlineEntryKind, InlineEntryState, InlineEntryUpdate,
@@ -152,8 +151,8 @@ impl Default for Model {
         let agents = vec![
             "Claude Code ACP".to_string(),
             "Codex ACP".to_string(),
-            "Mock ACP Agent".to_string(),
             "Gemini ACP".to_string(),
+            "Mock ACP Agent".to_string(),
             "Claude Code SDK".to_string(),
         ];
 
@@ -546,18 +545,19 @@ impl Model {
                 backends::claude_code_acp::ClaudeCodeAcpBackend::new().command_name(),
             ),
             backends::is_available(backends::codex_acp::CodexAcpBackend::new().command_name()),
-            backends::is_available(crate::backends::mock::binary_path()),
             backends::is_available(backends::gemini_acp::GeminiAcpBackend::new().command_name()),
+            backends::is_available(crate::backends::mock::binary_path()),
+            backends::is_available(backends::claude::ClaudeBackend::new().command_name()),
         ]
     }
 
     pub fn get_backend(&self) -> Box<dyn AgentBackend + Send> {
         match self.selected_agent_index {
             0 => Box::new(backends::claude_code_acp::ClaudeCodeAcpBackend::new()),
             1 => Box::new(backends::codex_acp::CodexAcpBackend::new()),
-            2 => Box::new(backends::mock::MockBackend::new()),
-            3 => Box::new(backends::gemini_acp::GeminiAcpBackend::new()),
-            4 => Box::new(ClaudeBackend::new()),
+            2 => Box::new(backends::gemini_acp::GeminiAcpBackend::new()),
+            3 => Box::new(backends::mock::MockBackend::new()),
+            4 => Box::new(backends::claude::ClaudeBackend::new()),
             _ => Box::new(backends::claude_code_acp::ClaudeCodeAcpBackend::new()),
         }
     }

src/backends/docs.md

@@ -126,16 +126,18 @@ pub fn get_backend(&self) -> Box<dyn AgentBackend + Send> {
     match self.selected_agent_index {
         0 => Box::new(backends::claude_code_acp::ClaudeCodeAcpBackend::new()),
         1 => Box::new(backends::codex_acp::CodexAcpBackend::new()),
-        2 => Box::new(backends::mock::MockBackend::new()),
-        3 => Box::new(backends::gemini_acp::GeminiAcpBackend::new()),
+        2 => Box::new(backends::gemini_acp::GeminiAcpBackend::new()),
+        3 => Box::new(backends::mock::MockBackend::new()),
+        4 => Box::new(backends::claude::ClaudeBackend::new()),
         _ => Box::new(backends::claude_code_acp::ClaudeCodeAcpBackend::new()),
     }
 }
 ```
 - Index 0: Claude Code ACP (via bunx/npx wrapper)
 - Index 1: Codex ACP (via bunx/npx wrapper)
-- Index 2: Mock ACP Agent (for testing)
-- Index 3: Gemini ACP (via bunx/npx wrapper)
+- Index 2: Gemini ACP (via bunx/npx wrapper)
+- Index 3: Mock ACP Agent (for testing)
+- Index 4: Claude commandline SDK (legacy approach)
 
 ### Installation Prompting