Let a bot take any colour

A bot's identity was one of seven hues, and the hue picked both its colour
and its stone shape. Now its colour is free and its stone is its own:

- `bots.color` holds any `#rrggbb`, `bots.stone` the flat-cut shape it's
  drawn on. `bots.hue` stays as the palette column they replaced, read only
  as a fallback; `src/scripts/move-bot-colour-to-owners.ts` backfills an
  install from it (safe to rerun).
- `src/utils/bot-color.ts` is the only place a colour is validated or
  resolved (`resolveBotColor`/`resolveBotStone` carry the old hue forward,
  `botColorNeedsPaperFace` flips the eyes to paper on a very dark body), and
  `src/utils/bot-stone-props.ts` gives every row its props, so a row saved
  before this still renders as it did.
- `BotStone` takes the colour as the body's SVG `fill`, the one documented
  exception to the token rule: an arbitrary hex has no token to point at.
  `UnreadDot` follows it.
- The picker keeps the palette tiles (still shape and colour together) and
  adds a native swatch and a hex field, so a custom colour keeps its stone.
  Same place as before: the header avatar's modal and Settings > Bots, for
  crew managers. The coordinator stays hue-less.
- A recolour reaches other open tabs through `pushBotUpdated`.

src/bots-queue/push-bot-updated.ts

@@ -1,3 +1,5 @@
+import BunSQLite from "@moduletrace/bun-sqlite";
+import type { BUN_SQLITE_COBBLE_BOTS } from "@/db/types/db";
 import grabBotAudience from "@/src/functions/backend/db/access/grab-bot-audience";
 import { logError } from "@/src/functions/backend/logger";
 import grabActiveBotTask from "@/src/functions/backend/db/bots/grab-active-bot-task";
@@ -61,6 +63,13 @@ async function push({
     workspace_ids,
 }: Params) {
     const audience = user_id ? [user_id] : await grabBotAudience({ bot_id });
+    /** Its colour and stone, so a recolour reaches every open tab. */
+    const identity = (
+        await BunSQLite.sql<BUN_SQLITE_COBBLE_BOTS>({
+            sql: `SELECT color, stone FROM bots WHERE id = ? LIMIT 1`,
+            values: [bot_id],
+        })
+    ).payload?.[0];
 
     for (const viewer_id of audience) {
         if (users && !users.has(String(viewer_id))) continue;
@@ -72,6 +81,8 @@ async function push({
                 data: {
                     id: Number(bot_id),
                     ...(await grabBotFace({ bot_id, user_id: viewer_id })),
+                    color: identity?.color || null,
+                    stone: identity?.stone || null,
                     ...(computer_id !== undefined ? { computer_id: computer_id || null } : {}),
                     ...(workspace_ids !== undefined ? { workspace_ids } : {}),
                     task: await grabActiveBotTask({ bot_id, user_id: viewer_id }),