docs(optimizable): add README index + refresh frontend-consistency tracker

The frontend-consistency-improvements.md was stale — it still listed
the 13 Tailwind-based ListViews as "to migrate" even though all 21
flagged modules shipped today (a2a43b1d5, 86c205ffc, 7d6a340b1, 52af8c0ce,
3e09ff66d). Rewrite to reflect the SHIPPED state and list the next
layer of open consistency work (i18n, Phosphor icons, cross-surface
theme parity).

New docs/optimizable/README.md is the master index. Consolidates:
  - 🔴 Release blocker: tier-patch revert (links memory entry)
  - 🟠 Tracked trackers: per-topic links with status
  - 🟡 Small open items without a dedicated file: module-structure
    audit, plan-inventory hygiene, memory-hygiene post-release,
    cross-surface theme parity
  - How-to: list of `pnpm run audit:*` commands for live metrics

Doesn't introduce new work items beyond what's already been discussed
this session — just gives them a home so future sessions can pick up
any one without re-discovery.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/optimizable/README.md

@@ -0,0 +1,97 @@
+# docs/optimizable — Known Improvements Register
+
+Per-topic tracking docs for known-but-unshipped improvements. Run
+`pnpm run audit:*` for live metrics on any item marked "OPEN" below.
+
+## 🔴 Release blockers
+
+### Tier-patch revert
+
+MANA_APPS were patched to `guest` tier locally on 2026-04-10 for pre-release
+testing. **Must revert before production release.** Production tiers
+are in commit `7df515434` but the working copy may still override.
+
+Context: memory entry `project_tier_patch_resolved.md`
+(`/Users/till/.claude/projects/.../memory/`). Check
+`packages/shared-branding/src/mana-apps.ts` and revert any
+`requiredTier: 'guest'` patches before cutting a release.
+
+## 🟠 Tracked open debt
+
+Each topic has its own tracker. Status as of 2026-04-22.
+
+| Topic | Tracker | Status |
+|---|---|---|
+| Frontend theming | [frontend-consistency-improvements.md](frontend-consistency-improvements.md) | Theming migration SHIPPED (ListViews, transition-all, a11y). i18n + icon bloat + cross-surface parity still OPEN. |
+| i18n coverage | [i18n-migration-inventory.md](i18n-migration-inventory.md) | 65 / 78 modules hardcode German. Per-module work. |
+| Test health | [test-health.md](test-health.md) | 34 / 653 tests failing (spaces-foundation WIP). 66 / 78 modules without any tests. |
+| Bundle size | [bundle-analysis.md](bundle-analysis.md) | /invoices split SHIPPED (-516 KB). Icons + layout OPEN. |
+| Foundation services | [foundation-layer-improvements.md](foundation-layer-improvements.md) | Contacts/Todo/Calendar architecture notes. |
+| AI Workbench audit | [ai-workbench-audit-2026-04-16.md](ai-workbench-audit-2026-04-16.md) | Point-in-time audit snapshot. |
+
+## 🟡 Small open items (no dedicated tracker yet)
+
+### Module-structure consistency audit
+
+Not every module has a DetailView. Some have master-detail (todo,
+notes, calendar), some are single-surface (calc, moodlit), some have
+standalone routes (presi/deck/[id]). An audit of which modules
+implement the full module-config pattern (ListView + DetailView +
+components/ + queries.ts + stores/) vs which are partial would give a
+sense of how strict the module SSoT actually is.
+
+**Suggested artefact:** `docs/optimizable/module-structure.md` +
+`scripts/audit-module-structure.mjs` listing which collections are
+defined vs missing per module.
+
+### Plan-inventory hygiene
+
+`docs/plans/` holds ~40 `.md` files. Some shipped (spaces-foundation,
+news-research, library M1), some are in-flight (library M2–M8, AI
+Workbench follow-ups, space-scoped data model Modell β), some are
+stale. No single "which plans are alive / dead / shipped" index.
+
+**Suggested artefact:** one-liner status table in `docs/plans/README.md`
+(SHIPPED / IN-FLIGHT / DRAFT / STALE with date).
+
+### Memory-hygiene post-release
+
+After the release (tier-patch revert + go-live), several memory
+entries become historical:
+
+- `project_tier_patch_resolved.md` — switch from "ACTIVE AGAIN for
+  testing" to "resolved". Or delete once the risk is gone.
+- `project_spaces_foundation.md` — mark "SHIPPED 2026-04-20" as
+  post-release state.
+- `project_news_research_module.md` / `project_library_module.md` /
+  `project_ai_workbench_rollout.md` — prune if follow-ups are no
+  longer relevant.
+
+No automation needed; a single post-release memory pass clears it.
+
+### Cross-surface theme parity
+
+See [frontend-consistency-improvements.md §6](frontend-consistency-improvements.md#6-cross-surface-theme-parity--open)
+for the landing / mobile / games audit.
+
+## How to find live numbers
+
+```bash
+pnpm run audit:all               # port-drift + i18n + test-coverage (summary)
+pnpm run audit:bundle            # bundle size + content hints
+pnpm run audit:icon-usage        # Phosphor icon inventory
+pnpm run audit:i18n-coverage     # per-module hardcoded-string scan
+pnpm run audit:port-drift        # CLAUDE.md ↔ code port drift
+pnpm run audit:test-coverage     # file-level test presence
+```
+
+`validate:all` (pre-push gate) is the complementary set — things that
+would fail a push, not just report. See `package.json` scripts.
+
+## Historical context
+
+Frontend-consistency tracker (this directory's original content) has
+been substantially completed: the 21 Tailwind ListViews, `transition-all`,
+a11y, neutral-palette, and theme-token migrations all shipped on
+2026-04-22. What remains is the next layer — i18n, icons, bundle,
+cross-surface — documented above.