Add poll chat command with reaction voting

docs/core-bridge.md

@@ -58,9 +58,10 @@ Event line:
 | `events.subscribe` | none | `{ "subscribed": true }`. The socket becomes an event subscriber. |
 | `state.get` | none | The current user, the guilds, and the channels. Cache-only. |
 | `voice.get` | optional `userId`, optional `guildId` | The voice channel and its members, or `channelId: null` |
-| `message.send` | `channelId`, `content` | `{ channelId, sent: true }` |
+| `message.send` | `channelId`, `content` | `{ channelId, messageId, sent: true }` |
 | `message.read` | `channelId`, `limit` | `{ cached, messages }`. Cache-only. |
 | `message.fetch` | `channelId`, `limit`, optional `before` or `after` | `{ fetched, messages }`. Fetches from Discord. |
+| `reaction.add` | `channelId`, `messageId`, `emoji` | `{ added: true }` |
 | `dm.send` | `userId`, `content` | `{ userId, channelId, sent: true }` |
 
 ## Validation rules
@@ -78,6 +79,8 @@ The core validates all input. The daemon cannot bypass these rules.
 - `before` and `after` must be snowflakes. They are mutually exclusive. `message.fetch` uses them
   to walk history.
 - `voice.get` accepts snowflakes only. It reads the client cache. It never joins a call.
+- `reaction.add` accepts a short emoji string without line breaks. It counts as an outbound action
+  for the rate limit.
 - A request line must not be larger than 64 KiB.
 
 ## Core rate limit
@@ -104,6 +107,7 @@ The core rate limit is a safety net. It does not replace the daemon pacing.
 | `CHANNEL_NOT_FOUND` | The channel is not in the client cache. |
 | `NOT_SENDABLE` | The channel type cannot receive messages. |
 | `SEND_FAILED` | Discord rejected the message. |
+| `REACTION_FAILED` | Discord rejected the reaction. |
 | `DM_UNAVAILABLE` | The client cannot create a DM channel. |
 | `NOT_SUPPORTED` | The client does not offer the internal action. |
 | `RATE_LIMITED` | The core rate limit rejected the action. |