fix(schemas): restore adcp_major_version in compact beta.0 request schemas

[garvitkaushik-123]

Summary

The 3.2.0-beta.0 frozen snapshots for buy-products, accept-proposal, and control-media-buy request schemas were published before adcp_major_version was added to the source schemas in #6647. Since these schemas set additionalProperties: false, conforming SDK buyers that emit both version fields (as the spec requires through 3.x) fail MCP input validation before the seller handler runs.

Subsequent betas (beta.1+) are not affected — the build picked up the source change correctly.

Changes

• 18 dist schema files across all beta.0 output paths (bundled, MCP, profiles/production, profiles/media-buy, model-context) patched to include adcp_major_version with the correct representation for each path type (fully inlined for bundled, $ref to $defs for MCP, absolute URL $ref for standalone)
• tests/compact-version-envelope.test.cjs — removed COMPACT_SCHEMAS_WITHOUT_MAJOR set that encoded the bug as expected behavior; all tools now expect adcp_major_version: 3
• tests/lint-version-envelope.test.cjs — added two regression guards:
  • Source lint: every request schema with adcp_version must also declare adcp_major_version
  • Dist lint: every versioned bundled dist schema must preserve both version fields

Verification

• compact-version-envelope.test.cjs passes (SDK validates all 7 lifecycle tools against the patched beta.0 source schemas)
• lint-version-envelope.test.cjs passes (4 tests including both new guards)
• Full root unit suite passes (67 files, 1052 tests)
• Manually verified the $ref targets in MCP schemas resolve correctly (the $defs["external:core/version-envelope.json"] block already contained adcp_major_version in beta.0 — only the property-level reference was missing)

Refs #6649

[bokelley]

This approach cannot merge because it rewrites files inside the already-published dist/schemas/3.2.0-beta.0 artifact. Released beta artifacts are immutable release records; the failing immutable-artifact check is intentional.

The source schemas and later beta artifacts already contain adcp_major_version, so there is no forward source fix to ship here. If beta.0 needs clarification, please re-scope this to a known-limitation note without changing dist/**/3.2.0-beta.0. Otherwise this PR should be closed.

[bokelley]

@bokelley's analysis is correct: the failing "Build and static checks" run enforces the immutable-artifact policy, and dist/schemas/3.2.0-beta.0 cannot be patched after publication regardless of what was missing before the freeze.

@garvitkaushik-123 — two paths forward:

1. Known-limitation note (if the gap needs a paper trail). Revert all dist/**/3.2.0-beta.0 changes and instead add a short note in the changelog or release notes documenting that the beta.0 frozen snapshots for buy-products, accept-proposal, and control-media-buy do not include adcp_major_version, and that SDK buyers should target beta.1 or later. No dist/ files change; the immutable-artifact check passes.

2. Close this PR. Since source schemas and all beta.1+ artifacts already carry adcp_major_version (via fix(media-buy): accept compact version envelope #6647), there is no active interop gap on the forward track. The beta.0 gap is a historical fact of the release, not something the dist tree can be retroactively corrected to address.

Either way, the current approach of editing dist/**/3.2.0-beta.0 cannot merge.

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Generated by Claude Code

[bokelley]

Closing because the proposed changes rewrite the published 3.2.0-beta.0 release artifact. The forward source and later beta artifacts already contain the field; beta.0 remains immutable. A documentation-only known-limitation follow-up can be opened separately if needed.

[garvitkaushik-123]

Thanks for clarifying, and sorry I missed the immutable-artifact policy. I understand why the PR was closed.