feat: add local agent MCP tools and optional source-grounded AI answers

apps/desktop/src-tauri/src/main.rs

@@ -1,9 +1,11 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
 
+mod ai_commands;
 mod model_download;
 mod semantic_commands;
 mod settings;
 
+use ai_commands::{generate_ai, prepare_ai_source, AiSession};
 use searchi_core::metrics::{MetricsMode, SearchMetrics, SearchResponse, TraceCollector};
 use searchi_core::{IndexReport, IndexStats, SearchIndex, SearchOptions, SearchResult};
 use semantic_commands::{
@@ -25,6 +27,7 @@ use tauri_plugin_global_shortcut::{GlobalShortcutExt, ShortcutState};
 use tauri_plugin_opener::OpenerExt;
 
 struct AppState {
+    ai: Arc<AiSession>,
     database: PathBuf,
     lexical: Arc<Mutex<SearchIndex>>,
     indexing: Arc<AtomicBool>,
@@ -461,6 +464,7 @@ fn main() {
                 }
             };
             app.manage(AppState {
+                ai: Arc::new(AiSession::default()),
                 database,
                 lexical,
                 indexing: Arc::new(AtomicBool::new(false)),
@@ -471,6 +475,8 @@ fn main() {
             Ok(())
         })
         .invoke_handler(tauri::generate_handler![
+            prepare_ai_source,
+            generate_ai,
             search,
             search_measured,
             stats,