chore: rebrand to GSD-redux/get-shit-done-redux

Mirror of code, issues, and PRs from the upstream gsd-build/get-shit-done,
which appears compromised or abandoned (maintainer unreachable since
2026-04-01; $GSD token linked to rug-pull).

- Adds rebrand notice block at top of English README
- Removes $GSD token badge and @gsd_foundation X badge (keeps Discord)
- Renames npm packages: get-shit-done-cc -> get-shit-done-redux,
  @gsd-build/sdk -> @gsd-redux/sdk
- Updates all repo URLs across docs, workflows, package.json, bin/
- Updates ci@gsd-build -> ci@gsd-redux in workflow git identities
- Leaves CHANGELOG and .changeset/* alone (historical, time-stamped)

assets/terminal.svg

@@ -38,7 +38,7 @@
     <!-- Prompt line -->
     <text class="text prompt" font-size="15" y="0">~</text>
     <text class="text dim" font-size="15" x="16" y="0">$</text>
-    <text class="text command" font-size="15" x="36" y="0">npx get-shit-done-cc</text>
+    <text class="text command" font-size="15" x="36" y="0">npx get-shit-done-redux</text>
 
     <!-- Banner -->
     <text class="text cyan" font-size="14" y="48" xml:space="preserve">   ██████╗ ███████╗██████╗</text>