§22 S1: release v0.40.0 — three-tier collection grain (breaking URL + migration 029)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -23,6 +23,86 @@ skip versions are the composition of each intervening adjacent
 release's steps in order — no A-to-B path is pre-computed beyond
 that.
 
+## 0.40.0 — 2026-06-05
+
+**Minor (breaking URL) — §22 three-tier refactor, slice S1: the *collection*
+grain. A deployment now hosts N projects, each owning one content repo and
+holding N RFC *collections*, each collection a typed corpus. S1 inserts the
+collection grain beneath today's project as the invisible default: the
+deployment runs exactly as before, now with a real collection layer and one
+extra `/c/<collection>/` URL segment. Per-corpus configuration (`type`,
+`initial_state`), entry keys, and membership move to the collection grain;
+no operator action is required beyond deploying.**
+
+See [`docs/design/2026-06-05-three-tier-projects-collections.md`](./docs/design/2026-06-05-three-tier-projects-collections.md)
+(Part A model, Part E / §A.6 migration strategy). The structural model (Parts
+A–D) is unaffected; the SPEC.md merge itself rides slice S6.
+
+Added:
+
+- **Migration `029_collections.sql`** — (1) a `collections` table
+  `(id, project_id, type, subfolder, initial_state, visibility, name,
+  registry_sha)` beneath `projects`; (2) the per-corpus fields (`type`,
+  `initial_state`) move **down** off `projects` onto the collection; (3) one
+  **default collection** per project (`id='default'` for the standard
+  single-project deployment, `subfolder` = repo root), inheriting the project's
+  type / initial_state / visibility; (4) the 13 entry-corpus tables re-key
+  `(project_id, slug)` → `(collection_id, slug)` via the migration-028 rebuild
+  pattern, each row mapped to its project's default collection; (5)
+  `project_members` generalises into **`memberships(scope_type ∈ {project,
+  collection}, scope_id, user_id, role, …)`** with the role enum collapsed to
+  `{owner, contributor}` (M2's `project_admin`→`owner`,
+  `project_contributor`→`contributor`; `project_viewer` folded into
+  `contributor` this pass — the read-only tier is deferred).
+- **`app/collections.py`** — collection resolution helpers
+  (`default_collection_id`, `collection_type`, `collection_initial_state`,
+  `project_of_collection`).
+- **`/c/<collection>/` URL segment** — the canonical entry route is now
+  `/p/<project>/c/<collection>/e/<slug>`. The project landing
+  `/p/<project>/` redirects into the project's single (default) collection
+  (C3.7); the deployment root `/` continues to redirect into the sole project
+  (C3.8).
+
+Changed:
+
+- **The registry mirror** writes a project's grouping-tier fields (name,
+  content_repo, visibility, config) to `projects` and the per-corpus fields
+  (`type`, `initial_state`) to its default collection; §22.4a type-immutability
+  is now enforced on the collection.
+- **Backend threading** — `auth.project_of_rfc` recovers a project by joining
+  `collections`; `auth.project_member_role` reads `memberships`;
+  `cache`/`api_*`/`funder` writers + readers key the 13 entry-corpus tables by
+  `collection_id` (the denormalised `project_id` tags on
+  `cached_prs`/`threads`/`changes`/`notifications`/`actions`/`pr_resolution_branches`
+  are unchanged). Serving stays project-scoped (collection = default); the
+  registry `.collection.yaml` reader and collection-aware serving land in S2.
+
+Breaking:
+
+- **`/p/<project>/e/<slug>` URLs gain a `/c/<collection>/` segment.** The
+  shipped v0.35.0 `/p/<project>/e/<slug>` form is preserved by a client-side
+  redirect into the default collection; the pre-multi-project `/rfc/<slug>` and
+  `/proposals/<n>` server 308s now target `/p/<default>/c/<default>/…`.
+
+> ### Upgrade steps (0.39.0 → 0.40.0)
+>
+> - A deployment **MUST** deploy this version with its migrations applied (the
+>   standard startup path runs `029_collections.sql` automatically); the
+>   migration seeds the default collection and re-keys existing entries with no
+>   data loss. No configuration change is required.
+> - Operators **SHOULD** be aware that the canonical entry URL is now
+>   `/p/<project>/c/default/e/<slug>`. Existing `/p/<project>/e/<slug>`,
+>   `/rfc/<slug>`, and `/proposals/<n>` links keep working (client redirect /
+>   server 308). External systems that hardcoded the old form **SHOULD** be
+>   updated to the collection-scoped form at their convenience.
+> - Deployments that pin the framework version **MUST** bump their version pin
+>   to `0.40.0`.
+
+Deferred (later slices): creating + navigating a second collection and the
+registry `.collection.yaml` reader (S2); the four-layer scope-role resolver and
+the `viewer` read tier (S3); invitation surfaces (S4); in-app create-project
+(S5); per-type surfaces, membership lifecycle, and the SPEC.md merge (S6).
+
 ## 0.39.0 — 2026-06-04
 
 **Minor — §22.13 step 1: the default-project-id re-stamp. A deployment can

VERSION

@@ -1 +1 @@
-0.39.0
+0.40.0

frontend/package.json

@@ -1,7 +1,7 @@
 {
   "name": "rfc-app-frontend",
   "private": true,
-  "version": "0.39.0",
+  "version": "0.40.0",
   "type": "module",
   "scripts": {
     "dev": "vite",