重构: agentic 架构(run_agentic_loop 抽 finish_round_exit + router 调用点 + provider_pool 亲和 enabled)

- run_agentic_loop: 抽 finish_round_exit + emit_ai_completed_once(6 退出点收敛)
- compress/title/knowledge_inject/project: router estimated_context+tier 调用点对齐
- provider_pool: 亲和加 model.enabled 过滤

src-tauri/src/commands/project.rs

@@ -652,6 +652,7 @@ async fn extract_description_via_llm(
         modalities: vec![Modality::Text],
         needs_tool_use: false,
         estimated_context: 0,
+        tier: None,
     };
     let scan_model = select_model_id(&scan_req, &pc.model_configs)
         .unwrap_or_else(|| pc.default_model.clone());
@@ -746,6 +747,7 @@ pub async fn scan_project_with_ai(
         modalities: vec![Modality::Text],
         needs_tool_use: false,
         estimated_context: 0,
+        tier: None,
     };
     let scan_model = select_model_id(&scan_req, &pc.model_configs)
         .unwrap_or_else(|| pc.default_model.clone());