refactor(kon): remove LLM command stubs — will be rewritten with llama-cpp-rs in Phase 3

- Remove 8 LLM command registrations from invoke_handler macro
- Delete commands/llm.rs stub file
- Remove pub mod llm from commands/mod.rs
- Build passes cleanly with cargo clippy

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src-tauri/src/lib.rs

@@ -75,15 +75,6 @@ pub fn run() {
             // Hardware
             commands::hardware::probe_system,
             commands::hardware::rank_models,
-            // LLM stubs
-            commands::llm::download_llm_model,
-            commands::llm::check_llm_model,
-            commands::llm::list_llm_models,
-            commands::llm::load_llm_model,
-            commands::llm::check_llm_engine,
-            commands::llm::llm_generate,
-            commands::llm::llm_extract_tasks,
-            commands::llm::llm_format_transcript,
         ])
         .run(tauri::generate_context!())
         .expect("error while running Kon");