feat(settings): add includeGitInstructions toggle

Adds an 'Include git instructions' toggle to the Agent Settings panel.
When disabled, sets CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONS=1 on the Claude
process to remove built-in commit and PR workflow guidance from its
system prompt. Resolves #209.

src-tauri/src/config.rs

@@ -37,6 +37,9 @@ pub struct ClaudeStartOptions {
 
     #[serde(default)]
     pub disable_cron: bool,
+
+    #[serde(default = "default_include_git_instructions")]
+    pub include_git_instructions: bool,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -174,6 +177,9 @@ pub struct HikariConfig {
 
     #[serde(default)]
     pub disable_cron: bool,
+
+    #[serde(default = "default_include_git_instructions")]
+    pub include_git_instructions: bool,
 }
 
 impl Default for HikariConfig {
@@ -221,6 +227,7 @@ impl Default for HikariConfig {
             task_loop_commit_prefix: "feat".to_string(),
             task_loop_include_summary: false,
             disable_cron: false,
+            include_git_instructions: true,
         }
     }
 }
@@ -265,6 +272,10 @@ fn default_task_loop_commit_prefix() -> String {
     "feat".to_string()
 }
 
+fn default_include_git_instructions() -> bool {
+    true
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, Default, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum BudgetAction {
@@ -360,6 +371,7 @@ mod tests {
         assert_eq!(config.task_loop_commit_prefix, "feat");
         assert!(!config.task_loop_include_summary);
         assert!(!config.disable_cron);
+        assert!(config.include_git_instructions);
     }
 
     #[test]
@@ -407,6 +419,7 @@ mod tests {
             task_loop_commit_prefix: "fix".to_string(),
             task_loop_include_summary: true,
             disable_cron: true,
+            include_git_instructions: false,
         };
 
         let json = serde_json::to_string(&config).unwrap();
@@ -425,6 +438,7 @@ mod tests {
         assert_eq!(deserialized.task_loop_commit_prefix, "fix");
         assert!(deserialized.task_loop_include_summary);
         assert!(deserialized.disable_cron);
+        assert!(!deserialized.include_git_instructions);
     }
 
     #[test]

src-tauri/src/wsl_bridge.rs

@@ -315,6 +315,11 @@ impl WslBridge {
                 cmd.env("CLAUDE_CODE_DISABLE_CRON", "1");
             }
 
+            // Disable built-in git instructions if requested
+            if !options.include_git_instructions {
+                cmd.env("CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONS", "1");
+            }
+
             cmd
         } else {
             // Running on Windows - use wsl with bash login shell to ensure PATH is loaded
@@ -372,6 +377,11 @@ impl WslBridge {
                 claude_cmd.push_str("CLAUDE_CODE_DISABLE_CRON=1 ");
             }
 
+            // Disable built-in git instructions if requested
+            if !options.include_git_instructions {
+                claude_cmd.push_str("CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONS=1 ");
+            }
+
             claude_cmd.push_str(
                 "claude --output-format stream-json --input-format stream-json --verbose",
             );