fix(dashboard): render canonical transcript artifacts - #1637

Summary

Dashboard transcript details now load canonical run artifacts when the run manifest lives under .internal/index.jsonl, so local AgentV result bundles render the transcript instead of a dangling-artifact error. The transcript toolbar's Expand all tool calls action now also opens the parent messages, making structured tool arguments and results visible immediately.

The parity dogfood also found larger UX gaps that are tracked separately rather than widened into this fix: direct raw/normalized artifact access, denser long-transcript navigation, and mobile clipping in the run detail surface.

Validation

• bun test apps/dashboard/src/components/transcript-timeline.test.tsx
• bun test apps/cli/test/commands/results/serve.test.ts --test-name-pattern "GET /api/runs/:filename/evals/:evalId/transcript|GET /api/runs/:filename/evals/:evalId/files|canonical .internal index transcript"
• bun --filter agentv typecheck
• cd apps/dashboard && bun run build
• Browser UAT with agent-browser against source Dashboard on local canonical transcript artifacts, missing transcript, empty transcript, Files raw transcript access, and 390x844 mobile-ish viewport

Evidence

Private evidence branch: https://github.com/EntityProcess/agentv-private/tree/evidence/av-2s7-20-dashboard-transcript-parity-2026-07-04

Reference inspected: https://github.com/EntityProcess/agentv-private/tree/evidence/entireio-transcript-viewer-reference-2026-07-02 at 4f4ea6d88c8daeacc436e19c67f8fa1c3aad99b5.

Related

Related: av-2s7.20
Follow-ups: av-2s7.22, av-2s7.23, av-2s7.24