feat: multi-branch template scanning from git repo + manual template selection

- Rewrite template.rs to scan all remote branches via git commands
  (git fetch/branch -r/ls-tree/git show/git archive)
- Add manual template picker dropdown in CreateForm UI
- Remove sentence-transformers/embed.py from Dockerfile (separate container)
- Clean up Gitea API approach, use local git repo instead
- Add chat panel and sidebar layout improvements

src/api/chat.rs

@@ -0,0 +1,53 @@
+use std::sync::Arc;
+use axum::{
+    extract::State,
+    http::StatusCode,
+    response::{IntoResponse, Response},
+    routing::post,
+    Json, Router,
+};
+use serde::Deserialize;
+
+use crate::llm::{ChatMessage, LlmClient};
+use crate::AppState;
+
+#[derive(Deserialize)]
+struct ChatRequest {
+    messages: Vec<SimpleChatMessage>,
+}
+
+#[derive(Deserialize)]
+struct SimpleChatMessage {
+    role: String,
+    content: String,
+}
+
+pub fn router(state: Arc<AppState>) -> Router {
+    Router::new()
+        .route("/chat", post(chat))
+        .with_state(state)
+}
+
+async fn chat(
+    State(state): State<Arc<AppState>>,
+    Json(input): Json<ChatRequest>,
+) -> Result<Json<serde_json::Value>, Response> {
+    let llm = LlmClient::new(&state.config.llm);
+    let messages: Vec<ChatMessage> = input
+        .messages
+        .into_iter()
+        .map(|m| ChatMessage {
+            role: m.role,
+            content: Some(m.content),
+            tool_calls: None,
+            tool_call_id: None,
+        })
+        .collect();
+
+    let reply = llm.chat(messages).await.map_err(|e| {
+        tracing::error!("Chat LLM error: {}", e);
+        (StatusCode::INTERNAL_SERVER_ERROR, e.to_string()).into_response()
+    })?;
+
+    Ok(Json(serde_json::json!({ "reply": reply })))
+}

src/api/mod.rs

@@ -1,3 +1,4 @@
+mod chat;
 mod kb;
 pub mod obj;
 mod projects;
@@ -31,6 +32,7 @@ pub fn router(state: Arc<AppState>) -> Router {
         .merge(timers::router(state.clone()))
         .merge(kb::router(state.clone()))
         .merge(settings::router(state.clone()))
+        .merge(chat::router(state.clone()))
         .route("/projects/{id}/files/{*path}", get(serve_project_file))
         .route("/projects/{id}/app/{*path}", any(proxy_to_service).with_state(state.clone()))
         .route("/projects/{id}/app/", any(proxy_to_service_root).with_state(state))

src/api/workflows.rs

@@ -11,6 +11,7 @@ use crate::AppState;
 use crate::agent::{AgentEvent, PlanStepInfo};
 use crate::db::{Workflow, ExecutionLogEntry, Comment, LlmCallLogEntry};
 use crate::state::AgentState;
+use crate::template;
 use super::{ApiResult, db_err};
 
 #[derive(serde::Serialize)]
@@ -21,6 +22,8 @@ struct ReportResponse {
 #[derive(Deserialize)]
 pub struct CreateWorkflow {
     pub requirement: String,
+    #[serde(default)]
+    pub template_id: Option<String>,
 }
 
 #[derive(Deserialize)]
@@ -36,6 +39,7 @@ pub fn router(state: Arc<AppState>) -> Router {
         .route("/workflows/{id}/report", get(get_report))
         .route("/workflows/{id}/plan", get(get_plan))
         .route("/workflows/{id}/llm-calls", get(list_llm_calls))
+        .route("/templates", get(list_templates))
         .with_state(state)
 }
 
@@ -72,6 +76,7 @@ async fn create_workflow(
     state.agent_mgr.send_event(&project_id, AgentEvent::NewRequirement {
         workflow_id: workflow.id.clone(),
         requirement: workflow.requirement.clone(),
+        template_id: input.template_id,
     }).await;
 
     Ok(Json(workflow))
@@ -191,3 +196,7 @@ async fn list_llm_calls(
     .map(Json)
     .map_err(db_err)
 }
+
+async fn list_templates() -> Json<Vec<template::TemplateListItem>> {
+    Json(template::list_all_templates().await)
+}