codegen: resync gen/ from EF 91d9e123

[heygen-rui-bot]

Auto-generated PR: a production deploy shipped an updated OpenAPI spec. This PR contains the CLI command definitions regenerated from the now-live prod spec in gen/.

What changed

New commands

• heygen avatar update -- PATCH /v3/avatars/{group_id}
• heygen brand kits create -- POST /v3/brand-kits
• heygen brand kits delete -- DELETE /v3/brand-kits/{brand_kit_id}
• heygen brand kits get -- GET /v3/brand-kits/{brand_kit_id}
• heygen brand kits update -- PATCH /v3/brand-kits/{brand_kit_id}

Public command surface only; commands hidden from --help are not listed.
Compared against heygen-cli main at b905aac41ed14f90499bd66fbb867aa9f6fb3afd.

If CI fails (e.g. missing examples), fix the issue and push to this branch.

Source commit: 91d9e12320b677017aceca9702bd220f9fb2ab48
Triggered by: https://github.com/heygen-com/experiment-framework/commit/91d9e12320b677017aceca9702bd220f9fb2ab48

[github-actions]

Command surface: additive only — 5 new command(s)

New commands — additive, nothing existing can break.

• heygen avatar update
• heygen brand kits create
• heygen brand kits delete
• heygen brand kits get
• heygen brand kits update

_{Reference only, never blocking. See RELEASE.md "Checking for Regressions" for how to read this.}

[heygen-rui-bot]

Superseded by sync/cli-codegen-5170d15e from EF commit 5170d15e8b735ff76c8fe23d04dd0cc21daec82d.