feat(task-019): add deterministic end-to-end demo stack flow

apps/backend/src/application/seed_data.py

@@ -4,6 +4,11 @@ from datetime import UTC, datetime
 from hashlib import sha256
 from uuid import NAMESPACE_URL, UUID, uuid5
 
+from src.application.demo_runtime import (
+    ensure_demo_bare_repository,
+    is_demo_mode,
+    resolve_demo_repository_path,
+)
 from src.domain.contracts import (
     PublishingRules,
     Role,
@@ -44,8 +49,9 @@ def seed_reference_data(repository: object) -> None:
         updated_at=SEED_TIMESTAMP,
     )
 
+    repository_url = _repository_url_for_seed()
     publishing_rules = PublishingRules(
-        repository_url="git@github.com:example/site.git",
+        repository_url=repository_url,
         production_branch="main",
         content_format="mdx",
         content_path_template="content/articles/{slug}.mdx",
@@ -85,15 +91,15 @@ def seed_reference_data(repository: object) -> None:
         updated_at=SEED_TIMESTAMP,
     )
 
-    publishing_yaml = """target: b2b_saas_blog
+    publishing_yaml = f"""target: b2b_saas_blog
 repository:
-  url: git@github.com:example/site.git
+  url: {repository_url}
   branch: main
 content:
   format: mdx
-  path_template: content/articles/{slug}.mdx
+  path_template: content/articles/{{slug}}.mdx
 assets:
-  path_template: public/articles/{slug}/{filename}
+  path_template: public/articles/{{slug}}/{{filename}}
 """
     transform_script = """export function transformArticle(article) {
   return {
@@ -121,6 +127,14 @@ assets:
     )
 
 
+def _repository_url_for_seed() -> str:
+    if not is_demo_mode():
+        return "git@github.com:example/site.git"
+    demo_repo_path = resolve_demo_repository_path()
+    ensure_demo_bare_repository(demo_repo_path)
+    return str(demo_repo_path)
+
+
 def _stable_uuid(value: str) -> UUID:
     return uuid5(NAMESPACE_URL, f"ai-content-pipeline:{value}")