feat: Oracle Canvas Component Schema and Qwen 3.6 integration (#31)

Co-authored-by: Sagnik <sagnik7896@gmail.com>
Reviewed-on: #31

backend/oracle/canvas_service.py

@@ -57,13 +57,37 @@ def _stringify(value: Any) -> str:
     return str(value) if value is not None else ""
 
 
+def _json_object(value: Any) -> dict[str, Any]:
+    if isinstance(value, dict):
+        return value
+    if isinstance(value, str) and value.strip():
+        try:
+            parsed = json.loads(value)
+            if isinstance(parsed, dict):
+                return parsed
+        except Exception:
+            logger.warning("canvas_service: failed to parse JSON object field; using empty object")
+    return {}
+
+
 def _normalize_component(component: dict[str, Any]) -> dict[str, Any]:
     normalized = deepcopy(component)
     normalized["componentId"] = _stringify(normalized.get("componentId"))
-    descriptor = normalized.get("dataSourceDescriptor") or {}
+    descriptor = _json_object(normalized.get("dataSourceDescriptor"))
     if descriptor.get("descriptorId") is not None:
         descriptor["descriptorId"] = _stringify(descriptor["descriptorId"])
     normalized["dataSourceDescriptor"] = descriptor
+    for field in (
+        "visualizationParameters",
+        "dataBindings",
+        "provenance",
+        "renderingHints",
+        "layout",
+        "accessControls",
+        "styleSignature",
+        "validationState",
+    ):
+        normalized[field] = _json_object(normalized.get(field))
     return normalized
 
 
@@ -105,7 +129,7 @@ def _deserialize_page_row(row: Any, components: list[dict[str, Any]]) -> dict[st
         "isShared": bool(row["is_shared"]),
         "headRevision": head_revision,
         "baseRevision": int(row["base_revision"]),
-        "sharingPolicy": row["sharing_policy"] or {
+        "sharingPolicy": _json_object(row["sharing_policy"]) or {
             "shareMode": "direct_fork_only",
             "allowReshare": False,
             "defaultForkVisibility": "private",