Support attaching a file / pasting a screenshot when creating a new ticket

The "New ticket" modal only took a plain-text message. It now matches the
existing reply box on an open ticket: a "Прикрепить файл" button, and Ctrl+V
paste of a clipboard screenshot attaches it directly. POST /api/tickets
switched from JSON to multipart/form-data to carry the optional file,
reusing the same saveAttachment/attachment-delivery path replies already use.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GteWhnWKTmnXcsd5jx6H7u

src/app/api/tickets/route.ts

@@ -4,6 +4,7 @@ import { NextResponse } from "next/server";
 import { z } from "zod";
 import { requireSession } from "@/lib/auth/require";
 import { listTickets, createManualTicket } from "@/lib/tickets/service";
+import { saveAttachment, AttachmentTooLargeError, MAX_ATTACHMENT_BYTES } from "@/lib/attachments/storage";
 
 export async function GET(request: Request) {
   const { session, response } = await requireSession();
@@ -18,19 +19,56 @@ const createSchema = z.object({
   subject: z.string().min(1).max(200),
   body: z.string().min(1).max(10_000),
   customerName: z.string().min(1).max(200),
-  customerEmail: z.string().email().optional(),
+  customerEmail: z.string().email().optional().or(z.literal("")),
 });
 
+// multipart/form-data rather than JSON — the modal supports an optional
+// attachment (incl. Ctrl+V screenshot paste), same as replying on an
+// existing ticket.
 export async function POST(request: Request) {
   const { session, response } = await requireSession();
   if (!session) return response;
 
-  const body = await request.json().catch(() => null);
-  const parsed = createSchema.safeParse(body);
+  const formData = await request.formData().catch(() => null);
+  if (!formData) return NextResponse.json({ error: "Invalid input" }, { status: 400 });
+
+  const parsed = createSchema.safeParse({
+    subject: formData.get("subject"),
+    body: formData.get("body"),
+    customerName: formData.get("customerName"),
+    customerEmail: formData.get("customerEmail") ?? undefined,
+  });
   if (!parsed.success) {
     return NextResponse.json({ error: "Invalid input" }, { status: 400 });
   }
 
-  const result = await createManualTicket(parsed.data);
+  const file = formData.get("file");
+  let attachment: { filename: string; mimeType: string; sizeBytes: number; storageKey: string } | undefined;
+  if (file instanceof File) {
+    if (file.size > MAX_ATTACHMENT_BYTES) {
+      return NextResponse.json({ error: "File too large" }, { status: 413 });
+    }
+    const buffer = Buffer.from(await file.arrayBuffer());
+    try {
+      const saved = await saveAttachment(buffer);
+      attachment = {
+        filename: file.name || "file",
+        mimeType: file.type || "application/octet-stream",
+        sizeBytes: saved.sizeBytes,
+        storageKey: saved.storageKey,
+      };
+    } catch (err) {
+      if (err instanceof AttachmentTooLargeError) {
+        return NextResponse.json({ error: "File too large" }, { status: 413 });
+      }
+      throw err;
+    }
+  }
+
+  const result = await createManualTicket({
+    ...parsed.data,
+    customerEmail: parsed.data.customerEmail || undefined,
+    attachment,
+  });
   return NextResponse.json(result, { status: 201 });
 }