Bug: Valid report&run metadata leads to `Report` tab being bricked with Server error 500 on evidently server/dashboard

[SebastianScherer88]

Issue

When I attach meta data to Report objects and/or the Report's run method (so the resulting Snapshot inherits the merged metadata), it breaks the dashboard's ability to parse those reports on the server, giving:

This seems to happen whenever i use non-string type values in the metadata that are officially supported as per here, i.e. this will not work:

metadata={'invalid-list':['test'],'invalid-dict':{'test-key':'test-value'}}

This works

metadata={'valid-string':'test'}

Oddly, this issue does NOT apply to datasets. The dashboard/server CAN resolve dict and list type values in dataset metadata and displays those correctly (if somewhat oddly with additional indices for each list entry):

System

Python 3.10.18
Evidently (client & server): 0.7.16

[GouravSingal-code]

@SebastianScherer88 are you or anyone working on this issue?

[GouravSingal-code]

Datasetmetadata contains the metadata: Dict[str, MetadataValueType] = {}

evidently/src/evidently/ui/service/datasets/metadata.py

Line 64 in 15b69bf

metadata: Dict[str, MetadataValueType] = {}

where as SnapshotMetadataModel contains the metadata: Dict[str, str]

evidently/src/evidently/sdk/models.py

Line 73 in 15b69bf

metadata: Dict[str, str]

we have to change the SnapshotMetadataModel.metadata to Dict[str, MetadataValueType] also.