Take the changelog block and schedule the apply

[sehkone]

Closes #46. Part of the consumer migration tracked in aicers/agent-instructions#16.

The pin file and the with:-less drift job were already here. Two things were not: nothing scheduled apply.yml, and repos.json upstream now lists changelog for deploy-core while this repository carried only workflow and rust.

The second cannot be delivered by the machinery that delivers everything else. render.py refuses a block whose marker pair is not already in the target, so the apply cannot bootstrap a block into a repository that has never had it. The marker pair arrives by hand once, and so does the CHANGELOG.md the block is about — upstream STYLE.md asks the block to follow the file rather than lead it, and this is the file arriving.

• CHANGELOG.md — an empty skeleton with an Unreleased heading.
• The changelog marker pair — after the rust block and before ## This crate, matching the order review-protocol uses and keeping the shared regions contiguous.
• 0.1.1 applied over all three regions — including dropping the old v<N> from every BEGIN marker, with the pin moved from v2 to 0.1.1.
• update-instructions.yml — calls apply.yml weekly, no with: and no secrets:, the same file review-protocol carries.

One pull request, deliberately

Every intermediate state is red: a marker pair the pin file does not list is a block this repository does not carry; a pin file naming changelog before the region is filled does not match the release; either one without CHANGELOG.md is a rule about a file that is not here.

The regions were not hand-edited

They were rewritten by apply_blocks.py against the 0.1.1 tree, so this is what the scheduled job would have written had it been able to. A dispatch after merging should find nothing to do.

Checked locally

• render.py check reports all three regions current against 0.1.1
• The blocks carried in AGENTS.md and the blocks listed in the pin file are the same three, so the drift check's other direction passes too
• No versioned BEGIN markers remain
• update-instructions.yml parses; markdownlint clean on AGENTS.md and CHANGELOG.md