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/components/general/task-list-item.tsx

@@ -6,7 +6,8 @@ import Button from "@moduletrace/twui/layout/Button";
 import type { TaskWithNames } from "@/src/types";
 import { AppContext } from "@/src/pages/__root";
 import BotAvatar from "@/src/components/general/bot-avatar";
-import type { BotFace, BotHue } from "@/src/dict/bot-dict";
+import type { BotFace } from "@/src/dict/bot-dict";
+import botStoneProps from "@/src/utils/bot-stone-props";
 import { TaskStatuses } from "@/src/dict/task-dict";
 import canManageCrew from "@/src/utils/rbac/can-manage-crew";
 import relativeTime from "@/src/utils/relative-time";
@@ -40,7 +41,7 @@ export default function TaskListItem({ task, onOpen, onStatusChange, busy }: Pro
         <Row className="w-full gap-3! flex-nowrap items-start px-3 py-3 border-0 border-b border-solid border-hairline last:border-b-0">
             <BotAvatar
                 image_media_id={task.bot_image_media_id}
-                hue={(task.bot_kind == "coordinator" ? null : task.bot_hue || null) as BotHue | null}
+                {...botStoneProps({ color: task.bot_color, stone: task.bot_stone, hue: task.bot_hue })}
                 face={(task.bot_face || "idle") as BotFace}
                 size={28}
             />