§22 S1: thread collection_id through backend + update tests (N=1 unchanged, 454 green)

- collections.py resolution helpers (default_collection_id, type, initial_state)
- registry mirror writes project grouping fields + default-collection corpus fields
- auth.project_of_rfc joins collections; project_member_role reads memberships
- cache/api_*/funder writers+readers re-keyed to collection_id (cached_prs + denormalised
  project_id tags unchanged); api_deployment reads type/initial_state from the default collection
- projects.py restamp detects bootstrap via collections; initial_state via collection
- tests updated to the three-tier schema; test_migration_028 retired (superseded by 029)
- add @S1 acceptance test (collection grain + N=1 serving)

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

backend/app/api_deployment.py

@@ -18,7 +18,7 @@ from typing import Any
 from fastapi import APIRouter, HTTPException, Request
 from fastapi.responses import RedirectResponse
 
-from . import auth, db, projects as projects_mod
+from . import auth, collections as collections_mod, db, projects as projects_mod
 from .config import Config
 
 
@@ -33,12 +33,21 @@ def make_router(config: Config) -> APIRouter:
         ).fetchone()
         # §22.5: enumerate only public + (member-)gated; unlisted is never listed.
         visible = set(auth.visible_project_ids(viewer))
+        # §22 three-tier: `type` is a per-corpus field on the (default) collection
+        # now; surface the default collection's type for each project.
         rows = db.conn().execute(
-            "SELECT id, name, type, visibility FROM projects "
+            "SELECT id, name, visibility FROM projects "
             "WHERE visibility != 'unlisted' ORDER BY name"
         ).fetchall()
         projects = [
-            {"id": r["id"], "name": r["name"], "type": r["type"], "visibility": r["visibility"]}
+            {
+                "id": r["id"],
+                "name": r["name"],
+                "type": collections_mod.collection_type(
+                    collections_mod.default_collection_id(r["id"])
+                ),
+                "visibility": r["visibility"],
+            }
             for r in rows
             if r["id"] in visible
         ]
@@ -60,8 +69,7 @@ def make_router(config: Config) -> APIRouter:
         # an unknown id). unlisted is readable by direct id.
         auth.require_project_readable(viewer, project_id)
         row = db.conn().execute(
-            "SELECT id, name, type, visibility, initial_state, config_json "
-            "FROM projects WHERE id = ?",
+            "SELECT id, name, visibility, config_json FROM projects WHERE id = ?",
             (project_id,),
         ).fetchone()
         if row is None:
@@ -71,13 +79,16 @@ def make_router(config: Config) -> APIRouter:
         except (ValueError, TypeError):
             cfg = {}
         dep = db.conn().execute("SELECT tagline FROM deployment WHERE id = 1").fetchone()
+        # §22 three-tier: type + initial_state moved down to the (default)
+        # collection in migration 029.
+        cid = collections_mod.default_collection_id(row["id"])
         return {
             "id": row["id"],
             "name": row["name"],
             "tagline": (dep["tagline"] if dep else "") or "",
-            "type": row["type"],
+            "type": collections_mod.collection_type(cid),
             "visibility": row["visibility"],
-            "initial_state": row["initial_state"],
+            "initial_state": collections_mod.collection_initial_state(cid),
             "theme": cfg.get("theme") or {},
         }
 
@@ -86,21 +97,27 @@ def make_router(config: Config) -> APIRouter:
     # is permanent, so external "RFC-0001" links and bookmarks land correctly.
     # nginx routes /rfc/ and /proposals/ to the backend so these are reached
     # before the SPA's index.html fallback.
+    # §22 three-tier (S1): the canonical entry route now carries the collection
+    # segment /p/<project>/c/<collection>/…. The legacy roots redirect through
+    # the default project's default collection.
     @router.get("/rfc/{slug}")
     async def redirect_old_rfc(slug: str) -> RedirectResponse:
         default_id = projects_mod.resolved_default_id(config)
-        return RedirectResponse(url=f"/p/{default_id}/e/{slug}", status_code=308)
+        cid = collections_mod.default_collection_id(default_id)
+        return RedirectResponse(url=f"/p/{default_id}/c/{cid}/e/{slug}", status_code=308)
 
     @router.get("/rfc/{slug}/pr/{pr_number}")
     async def redirect_old_rfc_pr(slug: str, pr_number: int) -> RedirectResponse:
         default_id = projects_mod.resolved_default_id(config)
+        cid = collections_mod.default_collection_id(default_id)
         return RedirectResponse(
-            url=f"/p/{default_id}/e/{slug}/pr/{pr_number}", status_code=308
+            url=f"/p/{default_id}/c/{cid}/e/{slug}/pr/{pr_number}", status_code=308
         )
 
     @router.get("/proposals/{pr_number}")
     async def redirect_old_proposal(pr_number: int) -> RedirectResponse:
         default_id = projects_mod.resolved_default_id(config)
-        return RedirectResponse(url=f"/p/{default_id}/proposals/{pr_number}", status_code=308)
+        cid = collections_mod.default_collection_id(default_id)
+        return RedirectResponse(url=f"/p/{default_id}/c/{cid}/proposals/{pr_number}", status_code=308)
 
     return router