chore: choose a safe main-to-next reconciliation method

[ss-o]

Decision required

The public main and next branches have diverged. A maintainer must choose a separately reviewed reconciliation method before work on #795 begins.

Owner: @ss-o

Public comparison

Observed 2026-07-18:

• next: 04bba1304898c214d64e2dd283516e788f6ba784
• main: 1291b3e5aea6e597b52f0bf28eafb31bd26cb77c
• merge base: ea4f7663d1ffce72f10a0c7013e8b67d16238c3c
• comparison: main is 15 commits ahead of and 9 commits behind next
• public compare: next...main

The active next protection requires linear history and signed commits.

Reviewed options

A — Rebuild and rewrite next

Rebuild next on top of main as a separately reviewed, fully signed linear history, then update next with force-with-lease.

• Preserves the linear-history rule.
• Rewrites the development branch.

B — Temporary linear-history exception

Temporarily exempt or disable required linear history, land one signed merge commit from main into next, then restore the rule.

• Preserves existing commit identities.
• Temporarily changes branch protection.
• Permanently adds a merge commit.

C — Content reconciliation (recommended pending maintainer approval)

Amend the gate from exact Git-object ancestry to content reconciliation, apply main's public tree changes to a linear reconciliation branch and pull request based on next, and verify equivalent content.

• Avoids rewriting next.
• Avoids a branch-protection mutation.
• Does not make the current main commit object an ancestor of next.

Option C is recommended for safety, pending explicit maintainer approval of the changed gate semantics.

Decision gate

This issue records options only. Do not create a reconciliation branch or pull request, change rules, merge, rewrite history, force push, or start the feature branch until the maintainer chooses an option and records the required verification.

[ss-o]

Maintainer decision: proceed with Option C.

The reconciliation will use a separately reviewed, signed, single-parent commit based on the captured next head. It will apply the captured main content with squash semantics, document overlap resolutions, and target next through a normal pull request. It will not rewrite a shared branch or change branch protection. Exact ancestry from the captured main commit is intentionally replaced by reviewed content/tree equivalence.

[ss-o]

Option C is complete, including signature recovery after GitHub's rebase merge rewrote the reviewed commits.

• Repaired next: c62e99fc4009bdd77891356c5b88b44ca0526d82
• Signed linear chain: 04bba130 → 31c8c94c → c62e99fc
• Exact remote-referenced commits pass git verify-commit
• Repaired and rewritten heads share tree c6f692879acbfa62738e1a276ee2b902ccfb8c5d
• No ruleset or repository-setting mutation

Closing this decision/reconciliation task as completed. The recurring signed merge-path problem remains tracked separately in #794.