Theater v0.4.0

This release focuses on integration-suite safety, CI ergonomics, deterministic
fixture data, and report diagnostics.

Highlights

Repo-aware reusable scenarios can now contribute selected slot-backed HTTP
auth declarations, reducing repeated flow-level auth registry entries without
introducing static credential composition or generic imports.
theater run can write JSON, JUnit, and Markdown sidecar artifacts from one
execution while preserving the run status after artifact rendering succeeds.
generate.date produces deterministic UTC date-only strings with the closed
iso and basic format enum.
Failed HTTP checks now include report-safe diagnostics with redacted request
URLs, selected response metadata, and bounded response previews across JSON,
text, Markdown, and JUnit projections.
Exact matching item selection is documented and hardened: has item where
asserts existence, while pick where selects exactly one item for later
selector steps, exports, logs, and expectations.
Local mock contract test guidance documents how downstream suites can keep
local external-service substitutes aligned with client contracts before
running full Theater local flows.
The JetBrains .thtr plugin is prepared for v0.4.0 and includes completion
and quick-documentation support for date generation.

Selected-library HTTP auth composition accepts only slot-backed auth entries.
Static bearer tokens, basic credentials, and static API key values remain
flow-owned or external configuration and are rejected when contributed by a
selected library.
run --format json, run --format junit, and report render remain
compatible. Sidecar output flags are additive.
generate.timestamp remains RFC3339-only. Date-only fixture values use the
new generate.date generator.
HTTP diagnostics are report-owned evidence. They are not action.http
outputs and cannot be exported through scenario dataflow.
pick where remains exact-one. It fails when zero or multiple items match.
Cleanup hooks and preflight guardrails are documented as future contracts
only; current YAML, .thtr, validation, runtime, report JSON, LSP, and native
JetBrains support do not execute those features yet.