[project evaluators] evaluator details — recent evaluations table

[mikeldking]

Part of #11650. Adds the Recent evaluations table from the Evaluator Details View design to the project evaluator details page: the latest results with label, score, and explanation, linking back to the evaluated artifact.

Current state

• The details page (ProjectEvaluatorDetailsPage.tsx) shows configuration only; the only way to see an evaluator's output today is to find annotated spans in the traces table.
• Backing rows exist (span_annotations / project_session_annotations written by the online-eval executor) but there is no evaluator-scoped GraphQL connection — that's the paginated recent-results connection in [online evals] expose evaluator result metrics over GraphQL #15531.
• Table primitives: components/table/; annotation label/score chips already exist in the annotation components used by ProjectAnnotationCountsCards / trace details.

Scope

• "Recent evaluations" table on the details page (Overview area, below configuration): timestamp, evaluated span/trace/session link, label chip (colored by optimization direction), score, explanation (truncated, full text on hover/expand)
• Rows navigate to the evaluated artifact (span in the tracing view, or session view for session evaluators)
• "View all" affordance that deep-links to the project traces/sessions view filtered to the evaluator's annotation name
• Pagination (load-more) over the connection; empty state for evaluators that haven't produced results

Dependencies

• [online evals] expose evaluator result metrics over GraphQL #15531 — recent-results connection
• [project evaluators] evaluator details page — LLM evaluator configuration #15307 — details page shell

Acceptance criteria

• The latest results are visible on the evaluator page without leaving it
• Clicking a row opens the evaluated artifact
• Works for span-, trace-, and session-target evaluators

Refs: #11650, design: Evaluator Details View (Aug 2026)