feat(iam): provision the LLM inference roles and assert project roles

The api-gw gates /v1/* on a capability named in the access token. ZITADEL
had no such role, so every inference call was 403 once the token came from
ZITADEL instead of Authentik.

- add llm:inference (Authentik spelling, keeps consumer manifests unchanged)
  and llm-inference (dash alias) to the project roles
- enable projectRoleAssertion on the project, which is what puts
  urn:zitadel:iam:org:project:roles into the access token; without it the
  role list never reaches the resource server

scripts/iam/zitadel-provision.py

@@ -80,6 +80,10 @@ ROLES = {
     "sqs-writers": "SQS/Temporal queue read/write access",
     "s3-users": "S3 read access",
     "s3-writers": "S3 read/write access",
+    # LLM gate for the api-gw. The colon form matches the Authentik-era
+    # permission string, so consumer manifests did not change.
+    "llm:inference": "LLM inference access (api-gw)",
+    "llm-inference": "LLM inference access (dash alias)",
 }
 
 _WEB = {"app_type_id": "OIDC_APP_TYPE_WEB", "auth_method_id": "OIDC_AUTH_METHOD_TYPE_BASIC"}
@@ -266,13 +270,26 @@ def _api(method: str, path: str, token: str, body: dict | None = None,
 
 def _ensure_project(token: str, name: str) -> str:
     code, d = _api("POST", "/management/v1/projects/_search", token, {})
+    project_id = ""
     for row in d.get("result") or []:
         if row.get("name") == name:
-            return row["id"]
+            project_id = row["id"]
+            break
+    if not project_id:
         code, d = _api("POST", "/management/v1/projects", token, {"name": name})
         if code not in (200, 201) or not d.get("id"):
             die(f"create project {name} failed: {code} {d}")
-    return d["id"]
+        project_id = d["id"]
+
+    # projectRoleAssertion puts the project roles into the ACCESS token as
+    # `urn:zitadel:iam:org:project:roles`. Without it the api-gw sees no
+    # llm:inference role and answers 403 for every inference call, even when
+    # the caller is correctly authorised in ZITADEL.
+    code, d = _api("PUT", f"/management/v1/projects/{project_id}",
+                   token, {"name": name, "projectRoleAssertion": True})
+    if code not in (200, 201):
+        die(f"enable projectRoleAssertion on {name} failed: {code} {d}")
+    return project_id
 
 
 def _ensure_roles(token: str, project_id: str, roles: dict[str, str]) -> None: