Build Cobble project structure from the handoff

- Remove the preset document suite (letters, emails, invoices, quotes,
  PDF generation, line items) with its routes, API handlers and tables
- Rebrand to Cobble: site data, Lato, handoff design tokens (light and
  dark) in main.css, brand assets in public/brand, ember stone logo and
  regenerated favicons
- Add bots, bot_messages, bot_tasks and bot_task_steps tables, regenerate
  DB types (BUN_SQLITE_COBBLE_*) and add a sample crew seed (seed:bots)
- Add the chat shell at /admin/bots: rail with pinned coordinator and
  user popover, bottom-anchored conversation with composer, working-on
  panel, and a send-message API scoped to the session user
- Add BotStone and Wordmark components, crew status and relative time
  utils with tests, and update AGENTS.md

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/pages/admin/bots/[bot_id]/(partials)/user-message-group.tsx

@@ -0,0 +1,18 @@
+import Stack from "@moduletrace/twui/layout/Stack";
+import type { MessageGroup } from "../(utils)/group-messages";
+import UserBubble from "./user-bubble";
+import GroupTimestamp from "./group-timestamp";
+
+/**
+ * Right-aligned ink bubbles, one timestamp under the group.
+ */
+export default function UserMessageGroup({ group }: { group: MessageGroup }) {
+    return (
+        <Stack className="w-full gap-1! items-end">
+            {group.messages.map((message) => (
+                <UserBubble key={message.id} text={message.text || ""} />
+            ))}
+            <GroupTimestamp at={group.at} />
+        </Stack>
+    );
+}