feat(registry): hard-cut META_REPO -> REGISTRY_REPO; wire mirror into startup/webhook/sweep

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/api_graduation.py

@@ -42,7 +42,7 @@ from fastapi import APIRouter, HTTPException, Request
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel, Field
 
-from . import auth, cache, db, entry as entry_mod
+from . import auth, cache, db, entry as entry_mod, projects as projects_mod
 from .bot import Actor, Bot
 from .config import Config
 from .gitea import Gitea, GiteaError
@@ -345,7 +345,7 @@ def make_router(
         # graduation PR's update_file call and the body to carry through
         # unchanged (meta-only keeps the body in the entry, §13.3).
         fetched = await gitea.read_file(
-            config.gitea_org, config.meta_repo, f"rfcs/{slug}.md", ref="main",
+            config.gitea_org, (projects_mod.default_content_repo(config) or ""), f"rfcs/{slug}.md", ref="main",
         )
         if fetched is None:
             raise HTTPException(409, f"Meta entry rfcs/{slug}.md not found on main")
@@ -479,7 +479,7 @@ def make_router(
             raise HTTPException(409, f"A claim PR is already open: #{already['pr_number']}")
 
         fetched = await gitea.read_file(
-            config.gitea_org, config.meta_repo, f"rfcs/{slug}.md", ref="main",
+            config.gitea_org, (projects_mod.default_content_repo(config) or ""), f"rfcs/{slug}.md", ref="main",
         )
         if fetched is None:
             raise HTTPException(409, f"Meta entry rfcs/{slug}.md not found on main")
@@ -495,7 +495,7 @@ def make_router(
         try:
             pr = await bot.open_claim_pr(
                 viewer.as_actor(),
-                org=config.gitea_org, meta_repo=config.meta_repo,
+                org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
                 slug=slug,
                 new_file_contents=new_contents, prior_sha=meta_sha,
             )
@@ -601,7 +601,7 @@ def make_router(
 
     async def _read_meta_entry(slug: str) -> tuple[entry_mod.Entry, str]:
         fetched = await gitea.read_file(
-            config.gitea_org, config.meta_repo, f"rfcs/{slug}.md", ref="main",
+            config.gitea_org, (projects_mod.default_content_repo(config) or ""), f"rfcs/{slug}.md", ref="main",
         )
         if fetched is None:
             raise HTTPException(409, f"Meta entry rfcs/{slug}.md not found on main")
@@ -656,7 +656,7 @@ async def _orchestrate(
         try:
             pr = await bot.open_graduation_pr(
                 actor,
-                org=config.gitea_org, meta_repo=config.meta_repo,
+                org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
                 slug=state.slug,
                 new_file_contents=graduated_contents,
                 prior_sha=meta_file_sha,
@@ -676,7 +676,7 @@ async def _orchestrate(
         try:
             await bot.merge_graduation_pr(
                 actor,
-                org=config.gitea_org, meta_repo=config.meta_repo,
+                org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
                 pr_number=state.new_pr_number,
                 head_branch=state.graduation_branch or "",
                 slug=state.slug, rfc_id=state.rfc_id,
@@ -738,7 +738,7 @@ async def _cleanup_unmerged(
     try:
         await bot.close_graduation_pr(
             actor,
-            org=config.gitea_org, meta_repo=config.meta_repo,
+            org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
             pr_number=state.new_pr_number,
             head_branch=state.graduation_branch or "",
             slug=state.slug, reason="graduation merge failed",
@@ -751,7 +751,7 @@ async def _cleanup_unmerged(
             await bot.delete_branch(
                 actor,
                 owner=config.gitea_org,
-                repo=config.meta_repo,
+                repo=(projects_mod.default_content_repo(config) or ""),
                 branch=branch_name,
                 slug=state.slug,
                 action_kind="delete_post_merge_branch",
@@ -861,7 +861,7 @@ async def _run_state_flip(
     try:
         pr = await bot.open_retire_flip_pr(
             actor,
-            org=config.gitea_org, meta_repo=config.meta_repo,
+            org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
             slug=slug, new_file_contents=new_contents, prior_sha=prior_sha,
             verb=verb, target_state=target_state,
         )
@@ -872,7 +872,7 @@ async def _run_state_flip(
     try:
         await bot.merge_retire_flip_pr(
             actor,
-            org=config.gitea_org, meta_repo=config.meta_repo,
+            org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
             pr_number=pr_number, head_branch=head_branch,
             slug=slug, verb=verb,
         )
@@ -881,12 +881,12 @@ async def _run_state_flip(
         # accumulate (mirrors graduation's `_cleanup_unmerged`).
         try:
             await bot.close_graduation_pr(
-                actor, org=config.gitea_org, meta_repo=config.meta_repo,
+                actor, org=config.gitea_org, meta_repo=(projects_mod.default_content_repo(config) or ""),
                 pr_number=pr_number, head_branch=head_branch,
                 slug=slug, reason=f"{verb} merge failed",
             )
             await bot.delete_branch(
-                actor, owner=config.gitea_org, repo=config.meta_repo,
+                actor, owner=config.gitea_org, repo=(projects_mod.default_content_repo(config) or ""),
                 branch=head_branch, slug=slug,
                 action_kind="delete_post_merge_branch",
                 reason=f"{verb} merge failed",