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/components/general/bot-stone.tsx

@@ -0,0 +1,63 @@
+import { twMerge } from "tailwind-merge";
+import type { BotFace, BotHue } from "@/src/dict/bot-dict";
+import { BotHueFillClasses } from "@/src/dict/bot-hue-classes-dict";
+import {
+    CoordinatorBodyPath,
+    StoneBodyPaths,
+    StoneViewBox,
+} from "@/src/data/stone-geometry";
+import BotStoneFace from "./bot-stone-face";
+
+type Props = {
+    /**
+     * The bot's identity hue. Omit (or `null`) for the coordinator, which
+     * renders hue-less: ink body, paper eyes, inverted in dark mode.
+     */
+    hue?: BotHue | null;
+    face?: BotFace;
+    size?: number;
+    /**
+     * Accessible name. Leave empty when a visible bot name sits beside the
+     * stone (the default), so the stone is decorative.
+     */
+    label?: string;
+    className?: string;
+};
+
+/**
+ * # Bot Stone
+ * @description A Cobble bot avatar: a stone with exactly one flat cut and two
+ * eyes. Never put it in a circle, ring or badge, or add an outline or shadow.
+ */
+export default function BotStone({
+    hue,
+    face = "idle",
+    size = 32,
+    label,
+    className,
+}: Props) {
+    const is_coordinator = !hue;
+    const body_path = hue ? StoneBodyPaths[hue] : CoordinatorBodyPath;
+    const body_class = hue ? BotHueFillClasses[hue] : "fill-ink";
+    const eye_fill = is_coordinator ? "fill-paper" : "fill-dark";
+    const eye_stroke = is_coordinator ? "stroke-paper" : "stroke-dark";
+
+    return (
+        <svg
+            width={size}
+            height={size}
+            viewBox={StoneViewBox}
+            role={label ? "img" : undefined}
+            aria-label={label || undefined}
+            aria-hidden={label ? undefined : true}
+            className={twMerge("shrink-0", className)}
+        >
+            <path d={body_path} className={body_class} />
+            <BotStoneFace
+                face={face}
+                fill_class={eye_fill}
+                stroke_class={eye_stroke}
+            />
+        </svg>
+    );
+}