Agent loop state machine refactor, unified LLM interface, and UI improvements

- Rewrite agent loop as Planning→Executing(N)→Completed state machine with
  per-step context isolation to prevent token explosion
- Split tools and prompts by phase (planning vs execution)
- Add advance_step/save_memo tools for step transitions and cross-step memory
- Unify LLM interface: remove duplicate types, single chat_with_tools path
- Add UTF-8 safe truncation (truncate_str) to prevent panics on Chinese text
- Extract CreateForm component, add auto-scroll to execution log
- Add report generation with app access URL, non-blocking title generation
- Add timer system, file serving, app proxy, exec module
- Update Dockerfile with uv, deployment config

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/timer.rs

@@ -0,0 +1,75 @@
+use std::sync::Arc;
+use sqlx::sqlite::SqlitePool;
+use crate::agent::{AgentEvent, AgentManager};
+use crate::db::Timer;
+
+pub fn start_timer_runner(pool: SqlitePool, agent_mgr: Arc<AgentManager>) {
+    tokio::spawn(timer_loop(pool, agent_mgr));
+}
+
+async fn timer_loop(pool: SqlitePool, agent_mgr: Arc<AgentManager>) {
+    tracing::info!("Timer runner started");
+
+    loop {
+        tokio::time::sleep(tokio::time::Duration::from_secs(30)).await;
+
+        if let Err(e) = check_timers(&pool, &agent_mgr).await {
+            tracing::error!("Timer check error: {}", e);
+        }
+    }
+}
+
+async fn check_timers(pool: &SqlitePool, agent_mgr: &Arc<AgentManager>) -> anyhow::Result<()> {
+    let timers = sqlx::query_as::<_, Timer>(
+        "SELECT * FROM timers WHERE enabled = 1"
+    )
+    .fetch_all(pool)
+    .await?;
+
+    let now = chrono::Utc::now();
+
+    for timer in timers {
+        let due = if timer.last_run_at.is_empty() {
+            true
+        } else if let Ok(last) = chrono::NaiveDateTime::parse_from_str(&timer.last_run_at, "%Y-%m-%d %H:%M:%S") {
+            let last_utc = last.and_utc();
+            let elapsed = now.signed_duration_since(last_utc).num_seconds();
+            elapsed >= timer.interval_secs
+        } else {
+            true
+        };
+
+        if !due {
+            continue;
+        }
+
+        tracing::info!("Timer '{}' fired for project {}", timer.name, timer.project_id);
+
+        // Update last_run_at
+        let now_str = now.format("%Y-%m-%d %H:%M:%S").to_string();
+        let _ = sqlx::query("UPDATE timers SET last_run_at = ? WHERE id = ?")
+            .bind(&now_str)
+            .bind(&timer.id)
+            .execute(pool)
+            .await;
+
+        // Create a workflow for this timer
+        let workflow_id = uuid::Uuid::new_v4().to_string();
+        let _ = sqlx::query(
+            "INSERT INTO workflows (id, project_id, requirement) VALUES (?, ?, ?)"
+        )
+        .bind(&workflow_id)
+        .bind(&timer.project_id)
+        .bind(&timer.requirement)
+        .execute(pool)
+        .await;
+
+        // Send event to agent
+        agent_mgr.send_event(&timer.project_id, AgentEvent::NewRequirement {
+            workflow_id,
+            requirement: timer.requirement.clone(),
+        }).await;
+    }
+
+    Ok(())
+}