fix: added default order by for list queries

[tushar-signoz]

Summary

• Adds a default ORDER BY timestamp DESC for list/raw queries (logs, traces) in the QueryRange API handler when no explicit order is specified
• This ensures that raw data listing endpoints (list views, exports, trace views) return results in a sensible newest-first order by default, rather than an undefined order

What changed

In pkg/querier/api.go, the QueryRange handler now calls queryRangeRequest.UseDefaultOrderBy() before executing the query. This method (already defined in querybuildertypesv5) applies a timestamp-descending default order to raw/list/trace request types when no order-by clause is present.

Test plan

• Verify list queries for logs return results ordered by timestamp descending by default
• Verify list queries for traces return results ordered by timestamp descending by default
• Verify that queries with an explicit order-by are not affected
• Verify aggregation/timeseries queries are not affected

🤖 Generated with Claude Code

[nityanandagohain]

@tushar-signoz please fix the tests