feat(commands): unify chat commands (#275)

* Chat commands: registry, access groups, Carbon

* Chat commands: clear native commands on disable

* fix(commands): align command surface typing

* docs(changelog): note commands registry (PR #275)

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Co-authored-by: Peter Steinberger <steipete@gmail.com>

src/auto-reply/send-policy.ts

@@ -17,7 +17,7 @@ export function parseSendPolicyCommand(raw?: string): {
   if (!raw) return { hasCommand: false };
   const trimmed = raw.trim();
   if (!trimmed) return { hasCommand: false };
-  const match = trimmed.match(/^\/send\b(?:\s+([a-zA-Z]+))?/i);
+  const match = trimmed.match(/^\/send(?:\s+([a-zA-Z]+))?\s*$/i);
   if (!match) return { hasCommand: false };
   const token = match[1]?.trim().toLowerCase();
   if (!token) return { hasCommand: true };