chore: rename remaining qwibitai/nanoclaw references to nanocoai/nanoclaw

Sweep of outbound strings, doc URLs, comments, and clone instructions
that were missed in the original org rename. One both-match case in
setup/lib/channels-remote.sh (URL detection) accepts either name so
existing forks with a `qwibitai` remote continue to resolve cleanly;
everywhere else is a straight rename.

Historical mentions left intact:
- CHANGELOG.md (v2.0.0 entry, frozen history)
- .claude/skills/add-gmail-tool/SKILL.md (pre-v2 qwibitai skill — historical)
- repo-tokens/badge.svg (auto-regenerated by update-tokens.yml)

setup/migrate-v2/discord-resolver.ts

@@ -66,7 +66,7 @@ async function getJson<T>(url: string, token: string, fetchImpl: FetchFn): Promi
   const res = await fetchImpl(url, {
     headers: {
       Authorization: `Bot ${token}`,
-      'User-Agent': 'NanoClaw-Migration (https://github.com/qwibitai/nanoclaw, 2.x)',
+      'User-Agent': 'NanoClaw-Migration (https://github.com/nanocoai/nanoclaw, 2.x)',
     },
   });
   if (!res.ok) {