docs(roadmap): tick TR.B6, mark Phase B complete

Settings joins about and history as migrated onto appShell() +
panel() + Keymap, closing out TR.B6 and Phase B (app-shell rollout)
entirely. Phase D (polish) unblocks as a result — it depended on B.

Author: JasonWarrenUK

docs/roadmaps/v5a-2606/enhanced.md

@@ -15,9 +15,9 @@ because the shell rollout and signature features build on them.
 |-------|--------------------------------------------------------------|--------|
 | **A** |        Foundations (theme, layout primitives, keymap)        | Complete |
 | **S** |         Security & dependency maintenance (Dependabot)       | Complete |
-| **B** |               App-shell rollout across screens               | In Progress (B1-B5 done) |
+| **B** |               App-shell rollout across screens               | Complete |
 | **C** | Signature UX features (help, toasts, progress, transitions)  | Ready |
-| **D** | Polish (palette, command palette, dark mode, schema display) | Blocked (needs B) |
+| **D** | Polish (palette, command palette, dark mode, schema display) | Ready (B done) |
 | **E** |       Tutorial & demo resources (Charm VHS recordings)       | Blocked (needs B/C) |
 
 > [!NOTE]
@@ -234,22 +234,34 @@ registry, and a header breadcrumb.
       `appShell()` + `panel()` + `Keymap`; unified the mapping-editor focus
       authority on the app-shell, replacing the previous weak two-panel focus
       model. Merged via PR #82.
-- [ ] **TR.B6** `refactor/config-screens-app-shell` — settings + history + about.
-      — **depends on TR.S2**. **In progress:** about and history migrated onto
-      `appShell()` + `panel()` + `Keymap`. History gets a two-pane layout
-      (Submissions list + Detail) mirroring the check-results precedent, with
-      the Validate/Cross-check/Delete keybar entries driven by `Keymap`
-      `when` guards on the current selection. Along the way, found and fixed a
-      real bug the migration surfaced: `SelectRenderable.selectedIndex` is
-      write-only on the real `@opentui/core` API (setter only, no getter) —
+- [x] **TR.B6** `refactor/config-screens-app-shell` — settings + history + about.
+      — **depends on TR.S2**. **Done:** about, history, and settings all
+      migrated onto `appShell()` + `panel()` + `Keymap`. History gets a
+      two-pane layout (Submissions list + Detail) mirroring the check-results
+      precedent, with the Validate/Cross-check/Delete keybar entries driven by
+      `Keymap` `when` guards on the current selection. Along the way, found
+      and fixed a real bug the migration surfaced: `SelectRenderable.selectedIndex`
+      is write-only on the real `@opentui/core` API (setter only, no getter) —
       reading it always returns `undefined`; the read path is the
       `getSelectedIndex()` method instead. Fixed in history.ts and added
       `getSelectedIndex()` to the shared test double
       (`tests/fixtures/tui/opentui.ts`) so this class of bug fails tests going
       forward. **Not yet fixed:** `mapping-builder.ts:340,350` and
       `mapping-editor.ts:557,584` (merged in TR.B5) still read
       `.selectedIndex` directly and have the same latent bug — flagged for a
-      follow-up fix, out of scope here. Settings remains for TR.B6.
+      follow-up fix, out of scope here. Settings is the most involved of the
+      three migrations: inline text/dropdown edit renderables, a two-press
+      reset-confirm, section-header skip-navigation, and directory fields that
+      round-trip through the file-picker all carried over unchanged. The
+      single status line that used to juggle five different messages
+      (nav bar, edit prompt, dropdown prompt, reset-confirm, "Saved!") now
+      routes through `shell.setFooter()` / `refreshFooter()`, mirroring
+      history's pattern; "Saved!" self-clears after 2s via `setTimeout`
+      instead of persisting until the next navigation. Save/Reset/Back
+      bindings carry `when: () => !this.editing` guards so they neither fire
+      nor show in the keybar mid-edit, replacing the old manual
+      `if (this.editing) return` gate. All TUI screens are now on the
+      app-shell framework — Phase B complete.
 
 ## Phase C — Signature UX features