feat: add disable_1m_context toggle to settings UI

Adds a new config option to expose the CLAUDE_CODE_DISABLE_1M_CONTEXT
environment variable through the settings sidebar, allowing users to
opt out of the extended 1M context window without manually setting
environment variables.

Closes #154

src-tauri/src/config.rs

@@ -28,6 +28,9 @@ pub struct ClaudeStartOptions {
 
     #[serde(default)]
     pub use_worktree: bool,
+
+    #[serde(default)]
+    pub disable_1m_context: bool,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -119,6 +122,9 @@ pub struct HikariConfig {
 
     #[serde(default)]
     pub use_worktree: bool,
+
+    #[serde(default)]
+    pub disable_1m_context: bool,
 }
 
 impl Default for HikariConfig {
@@ -152,6 +158,7 @@ impl Default for HikariConfig {
             budget_warning_threshold: 0.8,
             discord_rpc_enabled: true,
             use_worktree: false,
+            disable_1m_context: false,
         }
     }
 }
@@ -259,6 +266,8 @@ mod tests {
         assert_eq!(config.budget_action, BudgetAction::Warn);
         assert!((config.budget_warning_threshold - 0.8).abs() < f32::EPSILON);
         assert!(config.discord_rpc_enabled);
+        assert!(!config.use_worktree);
+        assert!(!config.disable_1m_context);
     }
 
     #[test]
@@ -292,6 +301,7 @@ mod tests {
             budget_warning_threshold: 0.75,
             discord_rpc_enabled: true,
             use_worktree: true,
+            disable_1m_context: false,
         };
 
         let json = serde_json::to_string(&config).unwrap();

src-tauri/src/wsl_bridge.rs

@@ -279,6 +279,11 @@ impl WslBridge {
                 }
             }
 
+            // Disable 1M context window if requested
+            if options.disable_1m_context {
+                cmd.env("CLAUDE_CODE_DISABLE_1M_CONTEXT", "1");
+            }
+
             cmd
         } else {
             // Running on Windows - use wsl with bash login shell to ensure PATH is loaded
@@ -319,6 +324,11 @@ impl WslBridge {
                 }
             }
 
+            // Disable 1M context window if requested
+            if options.disable_1m_context {
+                claude_cmd.push_str("CLAUDE_CODE_DISABLE_1M_CONTEXT=1 ");
+            }
+
             claude_cmd.push_str(
                 "claude --output-format stream-json --input-format stream-json --verbose",
             );