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+---
+phase: "16.2"
+slug: "plugin-provided-field-types-and-the-blog-editor-formwidget"
+# status lifecycle: draft (seeded by plan-phase) → validated (set by validate-phase §6)
+# audit-milestone §5.5 distinguishes NOT-VALIDATED (draft) from PARTIAL (validated + nyquist_compliant: false) (#2117)
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: "2026-10-09"
+---
+
+# Phase 16.2 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | Go `testing` (+ testify); admin vitest 3.2.7 + happy-dom; sm-journal-plugin vitest 3.2.7 (new, Wave 0); vue-journal-layer `node --test` |
+| **Config file** | `admin/vitest.config.ts`; `../sm-journal-plugin/vitest.config.ts` (Wave 0); `../vue-journal-layer/package.json` `test` script |
+| **Quick run command** | `go test -short ./modules/pact ./modules/cabana -run 'FieldType\|Plugin'` |
+| **Full suite command** | `go vet ./... && go test -short ./...` (summercms.go); `npm --prefix admin test`; `go -C ../sm-journal-plugin vet ./... && go -C ../sm-journal-plugin test -short ./... && npm --prefix ../sm-journal-plugin test`; `npm --prefix ../vue-journal-layer test` |
+| **Estimated runtime** | ~120 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** `go vet` + `go test -short` for the touched packages, plus the touched vitest file
+- **After every plan wave:** every full-suite command above
+- **Before `/msd-verify-work`:** full suites green, `bash scripts/check-admin-dist.sh`, `bash scripts/check-admin-openapi.sh --check`, the plugin `check-dist.sh`, `go test ./cmd/summer -run TestDocsTree`, and the human Docker-host run of the testcontainers suites
+- **Max feedback latency:** 120 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Threat Ref | Secure Behavior | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|------------|-----------------|-----------|-------------------|-------------|--------|
+| TBD | — | — | D-11 | — | Alias collision fails boot | unit | `go test -short ./modules/cabana -run TestFieldTypeRegistry` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-12.1 | — | Unknown plugin key fails boot | unit | `go test -short ./modules/cabana -run TestFieldTypeOptions` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-12.2 / D-10 | XSS | CheckHTML refuses per locale → 422 | unit | `go test -short ./modules/cabana -run TestFieldTypeDecode` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-03 | — | Untouched value writes nothing | unit | `go test -short ./modules/cabana -run TestFieldTypeUntouched` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-12.4 | — | List column uses plugin formatter | unit | `go test -short ./modules/cabana -run TestFieldTypeListValue` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-13 / D-15 | — | Schema/OpenAPI/TS in sync | unit + script | `bash scripts/check-admin-openapi.sh --check` | ✅ | ⬜ pending |
+| TBD | — | — | D-13 | — | PluginField binds value, emits on summer-change | vitest | `npm --prefix admin test -- PluginField` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-18 | upload | Auth, CSRF, permission, scope, size cap, type allowlist | unit | `go test -short ./modules/cabana -run TestFieldUpload` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-07 | — | Markdown post served as content_html | unit | `go -C ../sm-journal-plugin test -short ./classes -run TestBlogEditorLoad` | ❌ W0 | ⬜ pending |
+| TBD | — | — | D-03 / D-04 | XSS | Element round-trips; rawHtml card shows escaped text | vitest | `npm --prefix ../sm-journal-plugin test` | ❌ W0 | ⬜ pending |
+| TBD | — | — | todo resave | — | Untouched re-save byte-identical | integration (Postgres) | `go -C ../sm-journal-plugin test -run TestPostsAdminResaveKeepsHTML ./...` | ✅ (tighten) | ⬜ pending |
+| TBD | — | — | D-17 | iframe | Embed allowlist, id regex, gate-first | node:test | `npm --prefix ../vue-journal-layer test` | ❌ W0 | ⬜ pending |
+| TBD | — | — | docs | — | README/docs identifiers exist | unit | `go test ./cmd/summer -run TestDocsTree` | ✅ | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `../sm-journal-plugin/package.json`, `package-lock.json`, `vite.config.ts`, vitest + happy-dom setup, `scripts/check-dist.sh`
+- [ ] `modules/cabana/field_type_test.go` — registry, options, decode/skip, list, upload
+- [ ] `admin/tests/form/PluginField.test.ts` — stub custom element
+- [ ] `../vue-journal-layer/tests/embeds.test.ts`
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Testcontainers Postgres suites | todo resave | No Docker on the dev machine | Run on a Docker host, as in 16.1 |
+| Editing imported posts on UAT | Phase goal | Real browser editing of live posts | Open an imported post, save untouched, then edit and save; compare columns |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 120s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending