Support Emoji interpolation in text tag

Author: dahlia

docs/concepts/text.md

@@ -138,6 +138,18 @@ The above code will create a text like this:
 
 > Hello, [@fedify@hollo.social](https://hollo.social/@fedify).
 
+### `Emoji` 
+
+*This API is available since BotKit 0.2.0.*
+
+If you put an `Emoji` object (provided by Fedify) inside the interpolation,
+it will be rendered as a custom emoji.  You usually get `Emoji` objects from
+the `Reaction.emoji` property.  For example:
+
+~~~~ typescript
+text`Here's a custom emoji: ${reaction.emoji}.`
+~~~~
+
 ### `URL` object
 
 If you put a `URL` object inside the interpolation, it will be rendered as a

src/text.ts

@@ -15,7 +15,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 import {
   type Actor,
-  type Emoji,
+  Emoji,
   getActorHandle,
   isActor,
   Link,
@@ -129,6 +129,7 @@ export class TemplatedText<TContextData>
       if (isText<TContextData>(v)) return v;
       if (v instanceof URL) return link(v);
       if (isActor(v)) return mention(v);
+      if (v instanceof Emoji) return customEmoji(v);
       return new PlainText(String(v));
     });
   }