feat: add discord reaction tool

src/config/config.ts

@@ -171,6 +171,8 @@ export type DiscordConfig = {
   mediaMaxMb?: number;
   /** Number of recent guild messages to include for context (default: 20). */
   historyLimit?: number;
+  /** Allow agent-triggered Discord reactions (default: false). */
+  enableReactions?: boolean;
 };
 
 export type SignalConfig = {
@@ -879,6 +881,7 @@ const ClawdisSchema = z.object({
       requireMention: z.boolean().optional(),
       mediaMaxMb: z.number().positive().optional(),
       historyLimit: z.number().int().min(0).optional(),
+      enableReactions: z.boolean().optional(),
     })
     .optional(),
   signal: z