[ENHANCEMENT]: Span kind filter uses inconsistent values (`kind == 'chain'` vs `span_kind == 'CHAIN'`)

[jash0803]

Is your feature request related to a problem? Please describe.

In the traces UI, the Kind column displays values like chain, but filtering requires using span_kind == 'CHAIN'. This mismatch between the displayed column value and the filter expression is confusing and non intuitive.

From a user perspective, it looks like filtering by kind == 'chain' should work, but it does not. Instead, a different field name and casing (span_kind == 'CHAIN') must be used, which is not discoverable from the UI.

Describe the solution you'd like

Align the filter field and value with what is shown in the table. Either:

• Allow filtering using kind == 'chain', or
• Clearly expose span_kind and its expected values in the column or filter suggestions, or
• Normalize casing and field names so the displayed value can be used directly in filters.

This would make filtering more intuitive and reduce confusion when exploring traces.