emojis! 🧑‍🎨 🎨 ✏️ (#2814)

everyone ❤️'s emojis:
https://dropbox.tech/application/dropbox-paper-emojis-and-exformation


https://github.com/tldraw/tldraw/assets/469604/8f99f485-de98-44d1-93cb-6eb9c2d87d99




### Change Type

- [x] `minor` — New feature

### Test Plan

1. Test adding lots of emojis!

### Release Notes

- Adds emoji picker to text fields.

packages/editor/src/lib/utils/debug-flags.ts

@@ -8,7 +8,7 @@ import { Atom, atom, react } from '@tldraw/state'
 // `true` by default in development and staging, and `false` in production.
 /** @internal */
 export const featureFlags: Record<string, DebugFlag<boolean>> = {
-	// canMoveArrowLabel: createFeatureFlag('canMoveArrowLabel'),
+	emojiMenu: createFeatureFlag('emojiMenu'),
 }
 
 /** @internal */
@@ -111,16 +111,16 @@ function createDebugValue<T>(
 	})
 }
 
-// function createFeatureFlag(
-// 	name: string,
-// 	defaults: Defaults<boolean> = { all: true, production: false }
-// ) {
-// 	return createDebugValueBase({
-// 		name,
-// 		defaults,
-// 		shouldStoreForSession: true,
-// 	})
-// }
+function createFeatureFlag(
+	name: string,
+	defaults: Defaults<boolean> = { all: true, production: false }
+) {
+	return createDebugValueBase({
+		name,
+		defaults,
+		shouldStoreForSession: true,
+	})
+}
 
 function createDebugValueBase<T>(def: DebugFlagDef<T>): DebugFlag<T> {
 	const defaultValue = getDefaultValue(def)