ci(release): refuse a skein release version below the provider floor

[androidand]

Problem

skein-release.yml takes the version from a workflow_dispatch input or a skein-v* tag and hands it straight to build.ts as OPENCODE_VERSION. That value is compiled in and goes out as the opencode/<version> User-Agent (packages/opencode/src/provider/provider.ts). Providers on the free tier refuse anything below 1.17.0.

So a release cut as 0.1.0-skein.1 — a perfectly natural "first release of the fork" number — would build, upload, and publish cleanly, and every free provider would reject the resulting binary. Nothing in the pipeline would have objected.

Fix

One new step after "Resolve version", gating on the scheme that keeps the version honest: <upstream version>-skein.<n>, where the base must equal the version in packages/opencode/package.json (the upstream we last synced to). Pinning the base to the sync makes the 1.17.0 floor follow for free, and it means the release name always says which upstream it carries.

A mismatch now names the remedy rather than shipping quietly:

'1.17.8-skein.1' has base 1.17.8 but packages/opencode/package.json says we are
synced to 1.18.18. Release 1.18.18-skein.<n>, or sync first.

Also refreshed the two stale 1.17.8-skein.1 examples in the comments and the workflow_dispatch input description, which pointed at a base the guard would now reject.

Testing

• Guard logic exercised against 8 inputs — accepts 1.18.18-skein.1 / -skein.12; rejects 0.1.0-skein.1 and 1.16.9-skein.1 (floor), 1.18.17-skein.1 (base != sync), and 1.18.18 / v1.18.18-skein.1 / 1.18.18-skein (shape).
• Workflow YAML parses.
• bun run fork:verify — 223/223 owned, 112/112 patched, 0 unregistered divergence.

🤖 Generated with Claude Code

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[github-actions]

Hey! Your PR title ci(release): refuse a skein release version below the provider floor doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

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