Extends scripts/ci/cli-telemetry-e2e.mjs (already used to verify the `add`
command's telemetry) to spawn the built `render` command against two
generated fixture compositions and assert on the captured PostHog batch,
rather than a unit fixture that stubs the browser or ffmpeg.
One fixture sets every probed property (audio and image elements present,
root/body CSS size deliberately mismatched from the declared composition
size, a skill flag, one injected environment override) and its pair sets
none, so each property is asserted on both its present-and-correct side and
its absent-or-zero side in the same pair of runs: audio_count, image_count,
root_body_mismatch and its delta bucket, authoring_skill_source,
hf_env_overrides, and ffmpeg/browser_version_major.
Co-authored-by: Miguel Ángel <miguel.sierra@heygen.com>
