feat: ✨ Add Reactions extension

app/extensions/reactions/page.mdx

@@ -0,0 +1,95 @@
+export const metadata = {
+    title: "Reactions Extension",
+    description: "The Reactions Extension allows users to react to posts with emojis",
+}
+
+# Reactions Extension
+
+The Reactions Extension allows users to express their reactions ("react") to posts with emojis. {{ className: 'lead' }}
+
+## Federation
+
+User reactions are (like every other entity) federated to all followers, and can be displayed to clients depending on the privacy settings of the associated [Note](/entities/note).
+
+## Entity Definition
+
+<Row>
+    <Col>
+        <Properties>
+            <Property name="extension_type" type="string" required>
+                Must be `pub.versia:reactions/Reaction`.
+            </Property>
+            <Property name="author" type="string" required>
+                URI of the [User](/entities/user) that is reacting.
+            </Property>
+            <Property name="object" type="string" required>
+                URI of the [Note](/entities/note) attached to the reaction.
+            </Property>
+            <Property name="content" type="string" required>
+                Emoji content of reaction. May also be arbitrary text, or [Custom Emoji](/extensions/custom-emojis) if supported.
+
+                Clients are encouraged to disfavour text in favour of emoji where possible.
+            </Property>
+        </Properties>
+    </Col>
+
+    <Col sticky>
+
+    ```jsonc {{ title: "Example Entity" }}
+    {
+        "id": "6f27bc77-58ee-4c9b-b804-8cc1c1182fa9",
+        "type": "Extension", // [!code focus:2]
+        "extension_type": "pub.versia:reactions/Reaction",
+        "uri": "https://example.com/actions/6f27bc77-58ee-4c9b-b804-8cc1c1182fa9",
+        "created_at": "2021-01-01T00:00:00.000Z",
+        "author": "https://example.com/users/6e0204a2-746c-4972-8602-c4f37fc63bbe", // [!code focus:3]
+        "object": "https://example.com/publications/f08a124e-fe90-439e-8be4-15a428a72a19",
+        "content": "😀",
+    }
+    ```
+    
+    </Col>
+</Row>
+
+## Extensions to Note
+
+The Reactions Extension extends the [Note](/entities/note) entity with the following fields:
+
+<Row>
+    <Col>
+        <Properties>
+            <Property name="reactions" type="array" required>
+                URI to a [Collection](/entities/collection) of the [Reactions](#entity-definition) attached to the note.
+            </Property>
+        </Properties>
+    </Col>
+
+    <Col sticky>
+
+    ```jsonc {{ title: "Example Note" }}
+    {
+        "id": "01902e09-0f8b-72de-8ee3-9afc0cf5eae1",
+        "type": "Note", // [!code focus]
+        "uri": "https://versia.social/notes/01902e09-0f8b-72de-8ee3-9afc0cf5eae1",
+        "created_at": "2024-06-19T01:07:44.139Z",
+        "author": "https://versia.social/users/018eb863-753f-76ff-83d6-fd590de7740a",
+        "category": "microblog",
+        "content": {
+            "text/plain": {
+                "content": "Bababooey."
+            }
+        },
+        "extensions": { // [!code focus:5]
+            "pub.versia:reactions": {
+                "reactions": "https://versia.social/notes/01902e09-0f8b-72de-8ee3-9afc0cf5eae1/reactions"
+            }
+        },
+        "group": "public",
+        "is_sensitive": false,
+        "mentions": [],
+    }
+
+    ```
+    
+    </Col>
+</Row>

components/Navigation.tsx

@@ -290,6 +290,8 @@ export const navigation: NavGroup[] = [
         links: [
             { title: "Custom Emojis", href: "/extensions/custom-emojis" },
             { title: "Likes", href: "/extensions/likes" },
+            { title: "Polls", href: "/extensions/polls" },
+            { title: "Reactions", href: "/extensions/reactions" },
             { title: "Share", href: "/extensions/share" },
             { title: "Vanity", href: "/extensions/vanity" },
             { title: "WebSockets", href: "/extensions/websockets" },