fix(km): read back mixed enum labels safely

apps/api/tests/test_knowledge_repository_read_model.py

@@ -7,7 +7,12 @@ import pytest
 from sqlalchemy.dialects import postgresql
 
 from src.db.models import KnowledgeEntryRecord
-from src.models.knowledge import EntrySource, EntryStatus, EntryType
+from src.models.knowledge import (
+    EntrySource,
+    EntryStatus,
+    EntryType,
+    KnowledgeEntryCreate,
+)
 from src.repositories.knowledge_repository import (
     _ASSET_TAXONOMY_KEYS,
     KnowledgeDBRepository,
@@ -277,3 +282,56 @@ def test_knowledge_enum_db_labels_match_deployed_postgresql_contract() -> None:
     assert str(_knowledge_enum_db_value(EntryStatus.PUBLISHED)) == (
         "'published'::entrystatus"
     )
+
+
+@pytest.mark.asyncio
+async def test_idempotent_create_reads_back_published_with_enum_safe_projection(
+) -> None:
+    class _CreatedId:
+        def scalar_one(self):
+            return "km-created"
+
+    class _CreateDb:
+        def __init__(self):
+            self.statements = []
+            self.results = [
+                _CreatedId(),
+                _MappingResult([
+                    _record(
+                        id="km-created",
+                        entry_type="ANTI_PATTERN",
+                        source="AI_EXTRACTED",
+                        status="published",
+                        related_incident_id="INC-TEST-ENUM",
+                        path_type="ansible_no_write_replay:test",
+                    ).__dict__
+                ]),
+            ]
+
+        async def execute(self, statement):
+            self.statements.append(statement)
+            return self.results.pop(0)
+
+    db = _CreateDb()
+    entry = await KnowledgeDBRepository(db=db).create(  # type: ignore[arg-type]
+        KnowledgeEntryCreate(
+            title="Enum-safe writeback",
+            content="Durable AI learning receipt",
+            entry_type=EntryType.ANTI_PATTERN,
+            category="AI automation",
+            source=EntrySource.AI_EXTRACTED,
+            status=EntryStatus.PUBLISHED,
+            related_incident_id="INC-TEST-ENUM",
+            path_type="ansible_no_write_replay:test",
+        )
+    )
+
+    assert entry.status is EntryStatus.PUBLISHED
+    readback_sql = str(
+        db.statements[1].compile(
+            dialect=postgresql.dialect(),
+            compile_kwargs={"literal_binds": True},
+        )
+    ).lower()
+    assert "cast(knowledge_entries.status as varchar)" in readback_sql
+    assert "cast(knowledge_entries.entry_type as varchar)" in readback_sql