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/harness/tools/bot/update-bot-tool.ts

@@ -1,9 +1,9 @@
 import { z } from "zod";
 import type { BUN_SQLITE_COBBLE_BOTS } from "@/db/types/db";
 import { AppData } from "@/src/data/app-data";
-import type { BotHue } from "@/src/dict/bot-dict";
 import grabCrewWorkers from "@/src/functions/backend/db/bots/grab-crew-workers";
 import updateBot from "@/src/functions/backend/db/bots/update-bot";
+import { paletteColor, resolveBotStone } from "@/src/utils/bot-color";
 import type { HarnessTool } from "../../types";
 
 type Params = {
@@ -24,7 +24,8 @@ type Args = {
 /**
  * Lets the coordinator change an existing crew member: its name, its
  * one-line job, and its core instructions (the start of its prompt in its
- * own chat and in every workspace). Its hue and picture stay as they are.
+ * own chat and in every workspace). Its colour, stone and picture stay as
+ * they are.
  * Workspace-only instructions have their own tool
  * (`set_bot_workspace_instructions`).
  */
@@ -71,7 +72,13 @@ export default function updateBotTool({ user_id, workers }: Params): HarnessTool
                 bot_id: worker.id,
                 name: args.name ?? worker.name ?? "Bot",
                 role: args.role ?? worker.role ?? "",
-                hue: (worker.hue || "ember") as BotHue,
+                /**
+                 * Never changed here: the user's pick is theirs. A bot saved
+                 * before colours were free keeps the colour it showed.
+                 */
+                color:
+                    worker.color || paletteColor({ hue: worker.hue }) || "#e4572e",
+                stone: resolveBotStone({ stone: worker.stone, hue: worker.hue }),
                 system_prompt: args.instructions ?? worker.system_prompt ?? "",
             });