feat(B-0852): credential persistence on USB ESP + boot-sequence auth-method picker — encrypted blob bound to USB UUID + operator passphrase Phase 1 (Aaron 2026-05-27)

docs/BACKLOG.md

@@ -399,6 +399,7 @@ are closed (status: closed in frontmatter)._
 - [ ] **[B-0839](backlog/P1/B-0839-artem-kirsanov-channel-substrate-capture-computational-neuroscience-1000-brains-composition-aaron-2026-05-26.md)** Artem Kirsanov computational-neuroscience YouTube channel — substrate capture (videos → code + research substrate) — composes with 1000 Brains (Hawkins) + Adinkras (Gates) + caustic bloom filters + Boltzmann machines as energy-based substrate (Aaron 2026-05-26)
 - [ ] **[B-0840](backlog/P1/B-0840-thermal-forgetting-as-root-axiom-update-join-gated-memory-architecture-private-encryption-budget-exception-amara-aaron-2026-05-26.md)** thermal-forgetting = root-axiom-update + join-gated-memory architecture + private-encryption-budget exception (4-keeper-rule final form) — substrate-engineering work landing Amara's 2026-05-26 ratification of B-0839.3 reservoir-computing-as-framework-architecture (Aaron + Amara 2026-05-26)
 - [ ] **[B-0844](backlog/P1/B-0844-zflash-agent-mode-native-implementation-close-doc-vs-implementation-gap-aaron-2026-05-26.md)** zflash --agent flag — native agent-driven auto-type challenge implementation closing the docstring-vs-actual-implementation gap; empirical anchor from 2026-05-26 USB-re-flash session (Aaron 2026-05-26)
+- [ ] **[B-0852](backlog/P1/B-0852-credential-persistence-on-usb-esp-plus-boot-sequence-auth-method-picker-encrypted-blob-bound-to-usb-uuid-plus-operator-passphrase-aaron-2026-05-27.md)** credential persistence on USB ESP + boot-sequence auth-method picker — encrypted blob bound to USB UUID + operator passphrase (Phase 1); removes gh-login-throttle on USB re-boot workflow (Aaron 2026-05-27)
 - [ ] **[B-0853](backlog/P1/B-0853-sigstore-cosign-artifact-signing-free-stuff-iso-containers-tarballs-backed-by-fulcio-rekor-aaron-2026-05-27.md)** sigstore/cosign artifact signing — free-stuff coverage for ISO + containers + tarballs + Nix substitutes (Fulcio CA + Rekor transparency log; OIDC-keyless via GitHub Actions); commercial CAs deferred for proprietary OS surfaces (Aaron 2026-05-27)
 - [ ] **[B-0854](backlog/P1/B-0854-zeta-install-sh-to-ace-install-zeta-migration-trajectory-package-json-style-declarative-manifest-like-scratch-and-sqlsharp-aaron-2026-05-27.md)** zeta-install.sh → `ace install zeta` migration trajectory — declarative `package.json`-style Ace manifest in Zeta repo (like `../scratch` and `../SQLSharp` already do); composes with B-0288 Ace CLI + B-0824 meta-PM + B-0816 ArgoCD-maximization + B-0742 distributable-POC pattern (Aaron 2026-05-27)