feat: add Atlas discovery chat UI and API route

- components/AtlasChat.tsx — conversational PRD discovery UI (violet theme)
- app/api/projects/[projectId]/atlas-chat/route.ts — proxy + DB persistence
- overview/page.tsx — show Atlas for new projects, Orchestrator once PRD done

Made-with: Cursor

app/api/projects/[projectId]/atlas-chat/route.ts

@@ -0,0 +1,164 @@
+import { NextRequest, NextResponse } from "next/server";
+import { getServerSession } from "next-auth/next";
+import { authOptions } from "@/lib/auth/authOptions";
+import { query } from "@/lib/db-postgres";
+
+const AGENT_RUNNER_URL = process.env.AGENT_RUNNER_URL ?? "http://localhost:3333";
+
+// ---------------------------------------------------------------------------
+// DB helpers — atlas_conversations table
+// ---------------------------------------------------------------------------
+
+let tableReady = false;
+
+async function ensureTable() {
+  if (tableReady) return;
+  await query(`
+    CREATE TABLE IF NOT EXISTS atlas_conversations (
+      project_id TEXT PRIMARY KEY,
+      messages   JSONB NOT NULL DEFAULT '[]'::jsonb,
+      updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+    )
+  `);
+  tableReady = true;
+}
+
+async function loadAtlasHistory(projectId: string): Promise<any[]> {
+  try {
+    await ensureTable();
+    const rows = await query<{ messages: any[] }>(
+      `SELECT messages FROM atlas_conversations WHERE project_id = $1`,
+      [projectId]
+    );
+    return rows[0]?.messages ?? [];
+  } catch {
+    return [];
+  }
+}
+
+async function saveAtlasHistory(projectId: string, messages: any[]): Promise<void> {
+  try {
+    await ensureTable();
+    await query(
+      `INSERT INTO atlas_conversations (project_id, messages, updated_at)
+       VALUES ($1, $2::jsonb, NOW())
+       ON CONFLICT (project_id) DO UPDATE
+         SET messages = $2::jsonb, updated_at = NOW()`,
+      [projectId, JSON.stringify(messages)]
+    );
+  } catch (e) {
+    console.error("[atlas-chat] Failed to save history:", e);
+  }
+}
+
+async function savePrd(projectId: string, prdContent: string): Promise<void> {
+  try {
+    await query(
+      `UPDATE fs_projects
+         SET data = data || jsonb_build_object('prd', $2, 'stage', 'architecture'),
+             updated_at = NOW()
+       WHERE id = $1`,
+      [projectId, prdContent]
+    );
+    console.log(`[atlas-chat] PRD saved for project ${projectId}`);
+  } catch (e) {
+    console.error("[atlas-chat] Failed to save PRD:", e);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// POST — send message to Atlas
+// ---------------------------------------------------------------------------
+
+export async function POST(
+  req: NextRequest,
+  { params }: { params: Promise<{ projectId: string }> }
+) {
+  const session = await getServerSession(authOptions);
+  if (!session?.user?.email) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  const { projectId } = await params;
+  const { message } = await req.json();
+  if (!message?.trim()) {
+    return NextResponse.json({ error: "message is required" }, { status: 400 });
+  }
+
+  const sessionId = `atlas_${projectId}`;
+
+  // Load conversation history from DB to persist across agent runner restarts
+  const history = await loadAtlasHistory(projectId);
+
+  try {
+    const res = await fetch(`${AGENT_RUNNER_URL}/atlas/chat`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        message,
+        session_id: sessionId,
+        history,
+      }),
+      signal: AbortSignal.timeout(120_000),
+    });
+
+    if (!res.ok) {
+      const text = await res.text();
+      console.error("[atlas-chat] Agent runner error:", text);
+      return NextResponse.json(
+        { error: "Atlas is unavailable. Please try again." },
+        { status: 502 }
+      );
+    }
+
+    const data = await res.json();
+
+    // Persist updated history
+    await saveAtlasHistory(projectId, data.history ?? []);
+
+    // If Atlas finalized the PRD, save it to the project
+    if (data.prdContent) {
+      await savePrd(projectId, data.prdContent);
+    }
+
+    return NextResponse.json({
+      reply: data.reply,
+      sessionId,
+      prdContent: data.prdContent ?? null,
+      model: data.model ?? null,
+    });
+  } catch (err) {
+    console.error("[atlas-chat] Error:", err);
+    return NextResponse.json(
+      { error: "Request timed out or failed. Please try again." },
+      { status: 500 }
+    );
+  }
+}
+
+// ---------------------------------------------------------------------------
+// DELETE — clear Atlas conversation for this project
+// ---------------------------------------------------------------------------
+
+export async function DELETE(
+  _req: NextRequest,
+  { params }: { params: Promise<{ projectId: string }> }
+) {
+  const session = await getServerSession(authOptions);
+  if (!session?.user?.email) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  const { projectId } = await params;
+  const sessionId = `atlas_${projectId}`;
+
+  try {
+    await fetch(`${AGENT_RUNNER_URL}/atlas/sessions/${sessionId}`, { method: "DELETE" });
+  } catch { /* runner may be down */ }
+
+  try {
+    await query(`DELETE FROM atlas_conversations WHERE project_id = $1`, [projectId]);
+  } catch { /* table may not exist yet */ }
+
+  return NextResponse.json({ cleared: true });
+}