ABI: audit Home private profile revision 4389ddee

Parent: #163 Depends on: #165, #168, #173

The active Home main revision is now 4389ddeea0445f28f400f86995435b473b8aa167. The strict live-source audit correctly rejects it because only exact revisions are supported, while a direct Git comparison shows zero changed files under packages/runtime/src/jsc relative to the immutable 7ed99c02 base.

Acceptance:

• Add an explicit home-private-4389ddee alias manifest naming the full revision and immutable base profile.
• Verify every one of the 58 source hashes and all 448 normalized declarations, locations, classifications, and calling conventions against the base inventory.
• Require zero source, declaration, signature, and calling-convention differences; reject any future mismatch.
• Run the real live Home checkout through the alias audit and combined compile-link-runtime fixture without touching unrelated Home worktree changes.
• Document the exact supported revision in the README, ABI guide, and Home integration guide.
• Link completion evidence into #163, #140, and #134.

This is an explicit alias decision, not a moving main profile or a relaxation of unknown-revision rejection.

Completed on main in 75d931a.

Evidence:

• The exact home-private-4389ddee manifest pins full revision 4389ddeea0445f28f400f86995435b473b8aa167 to the immutable home-private-7ed99c02 source contract.
• git diff 7ed99c02..4389ddee -- packages/runtime/src/jsc reports zero changed files.
• zig build test-home-private-abi -Doptimize=Debug -Dhome-private-abi-profile=home-private-4389ddee -Dhome-source-root=/Users/chris/Code/Home/lang verifies all 58 source hashes, 448 declarations and conventions, then passes the 69/69 combined runtime fixture.
• The unrelated dirty Home packages/ts_checker/src/check.zig and .claude/ state were not touched.
• README, ABI guide, and Home integration guide now name the fourth exact supported revision and show the live-profile audit command.