feat: add ability to configure the agent (also theme switcher) (#3)

### Explanation

_No response_

### Issue

_No response_

### Attestations

- [ ] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

_No response_

### Versioning

_No response_

Reviewed-on: #3
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src-tauri/src/lib.rs

@@ -1,4 +1,5 @@
 mod commands;
+mod config;
 mod types;
 mod wsl_bridge;
 
@@ -13,6 +14,7 @@ pub fn run() {
         .plugin(tauri_plugin_dialog::init())
         .plugin(tauri_plugin_opener::init())
         .plugin(tauri_plugin_shell::init())
+        .plugin(tauri_plugin_store::Builder::new().build())
         .manage(bridge)
         .invoke_handler(tauri::generate_handler![
             start_claude,
@@ -21,6 +23,8 @@ pub fn run() {
             is_claude_running,
             get_working_directory,
             select_wsl_directory,
+            get_config,
+            save_config,
         ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");