docs: add vault-tab management surfaces revamp spec

Brainstormed design covering UX revamp of all four in-vault admin
panes (Settings, Devices, Trash, History) to match the fullscreen
visual language. Closes functional gaps along the way: per-device
session-timeout UI, revoke button surfacing, SHA256 fingerprint +
added-by display, per-item purge countdown, and a new history
index pane.

Item history uses option A (aggregate existing field_history per
item) — no new core storage, no schema change. Ships in v0.5.x
inside the current vault.ts shell; Phase 3 shell rearchitecture and
Phase 4 command palette deferred to their own rounds.

Roadmap entry reconciled to point at the spec.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ROADMAP.md

@@ -29,8 +29,8 @@ These are specced and either in progress or immediately queued:
 - **Phase 3: vault-tab shell** — fullscreen sidebar with nav sections, pane routing  
   Spec: `docs/superpowers/specs/2026-04-27-relicario-vault-tab-design.md`
 - **Phase 4: command palette** — ⌘K global search + action dispatch across the vault tab
-- **Trash & history UI** — trash view, item history viewer, field-history viewer
-- **Device manager UI** — device registration + revocation in vault tab
+- **Vault-tab management surfaces revamp** — UX revamp of all four in-vault admin panes (Settings, Devices, Trash, History) to match the fullscreen visual language; closes functional gaps (session-timeout UI, revoke button surfacing, fingerprint display, purge countdown, history index). Aggregates existing `field_history` per item — no new core storage. Ships in v0.5.x.  
+  Spec: `docs/superpowers/specs/2026-05-23-vault-tab-management-surfaces-revamp-design.md`
 - **CLI restructure** — subcommand reorganisation, interactive TUI mode  
   Spec: `docs/superpowers/specs/2026-05-04-cli-restructure-design.md`
 - **Extension restructure** — bundle / message-routing cleanup