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)

docs/adr/0003-model-catalog-module.md

@@ -30,8 +30,8 @@ The catalog owns:
 - agent → dynamic-routing default tier mapping
 
 The canonical file lives in a location both packages ship:
-- repo root package (`get-shit-done-cc`) includes it
-- standalone SDK package (`@gsd-build/sdk`) includes it
+- repo root package (`get-shit-done-redux`) includes it
+- standalone SDK package (`@gsd-redux/sdk`) includes it
 
 Both CJS and SDK load this exact file. Neither package keeps its own independent list.