chore(scripts): add Discord bot permission diagnostic

One-off script that logs in with each configured Discord bot token and prints
the bot member's effective permission bits per guild, so capability claims can
be verified empirically instead of inferred from intents.

Co-Authored-By: Claude Opus 4 <noreply@anthropic.com>

src/channels/discord.test.ts

@@ -1226,7 +1226,9 @@ describe('chunkForDiscord', () => {
     const chunks = chunkForDiscord(text, 9);
     for (const c of chunks) {
       // No chunk should start or end mid surrogate pair.
-      expect(c.charCodeAt(0) >= 0xdc00 && c.charCodeAt(0) <= 0xdfff).toBe(false);
+      expect(c.charCodeAt(0) >= 0xdc00 && c.charCodeAt(0) <= 0xdfff).toBe(
+        false,
+      );
       const last = c.charCodeAt(c.length - 1);
       expect(last >= 0xd800 && last <= 0xdbff).toBe(false);
     }