Align artifact API docs and extend firstN edge-case tests (#747)

Refactor e2e test helpers and update test cases

Simplify chat handler and conversation flow logic

Refactor conversation flow logic and update API handler

Refactor chat component imports to use consistent path aliases

remove code runner (#746)

Simplify debug e2e chat tests with shared setup helpers

Stabilize debug e2e tests around assistant message lifecycle

Wait for non-empty assistant text in e2e debug flows

Refactor e2e session answer tests to reduce duplication and improve maintainability

Use content-based assistant matching in flaky e2e debug tests

Make e2e debug/regenerate tests assistant-message aware

Stabilize e2e chat assertions for persisted user messages

Fix workspace auth, default invariants, and reorder handling

Refactor chat session and workspace APIs for improved consistency and error handling