fix: fail safe on missing workspace revisions

deploy/workspaces/psd.yaml.example

@@ -1,40 +1,39 @@
-language: en
+workspace:
+  schema_version: 3
+  id: psd-clinical
+  name: PSD Clinical
+  description: Example PSD-oriented WorkspaceV3 descriptor.
+  language: en
 
 dwh:
-  type: thoth_rest
-  database:
-    database: ${THT_DB_NAME}
-    schema: datawarehouse
-  endpoint:
-    base_url: ${THT_DWH_REST_URL}
-    api_key: ${THT_DWH_API_KEY}
-    ssl_ca: ${THT_SSL_CA}
+  engine: postgres
+  database: postgres
+  schema: datawarehouse
+  supported_transports:
+    - postgres_direct
+    - rest_api
 
-roots:
-  artifacts: /data/workspaces/generic/artifacts
-  indexes: /data/workspaces/generic/indexes
-  sessions: /data/workspaces/generic/sessions
-
-evidence:
-  source_root: ${THT_DOCS_ROOT}
-  evidence_dir: evidence
-
-resources:
-  vector:
-    # Schema-v3 descriptors publish only the collection identity; the runtime renderer
-    # supplies this fixed internal Qdrant architecture.
+semantic_index:
+  vector_store:
     engine: qdrant
-    base_url: http://qdrant:6333
-    collection: generic
-  embeddings:
-    # Embeddings are fixed to the internal Ollama service for schema-v3 descriptors.
+    collection: psd-clinical
+    dimensions: 1024
+    distance: cosine
+  embedding:
     provider: ollama_internal
-    base_url: http://embedding:11434
     model: qwen3-embedding:0.6b
     dimensions: 1024
 
-execution:
-  allow: [cte_test, explain, preview, aggregate, export]
-  max_preview_rows: 10
-  max_export_rows: 100000
-  statement_timeout_ms: 30000
+llm_policy:
+  default: zai/glm-5.2
+  allowed:
+    - zai/glm-5.2
+
+diagnostics:
+  dwh_rest:
+    method: GET
+    path: /health
+    auth: none
+    response:
+      database: database
+      schema: schema