Add entire trail merge subcommand

[matthiaswenz]

https://entire.io/gh/entireio/cli/trails/604

Summary

Adds an entire trail merge subcommand that merges a trail's branch into its base, after first checking the trail is mergeable. A --dry-run flag reports mergeability without performing the merge.

The Entire API already exposes the needed endpoints (GET .../{number}/mergeability and POST .../{number}/merge); this wires the CLI up to them.

Behavior

• Resolves the trail from --trail (number, id, or branch), or the current branch's trail when omitted.
• Always checks mergeability first and prints a readiness summary (approvals, CI checks, up-to-date with base).
• Refuses to merge when the trail isn't mergeable, listing the blockers in the same order the server evaluates its gates.
• --dry-run stops after the check. It exits non-zero when the trail isn't mergeable, so it can gate CI.
• On a real run, performs the merge and verifies the server's ok:true signal (mirroring deleteTrailByNumber) before reporting the merge commit SHA.

$ entire trail merge --help
Merge a trail's branch into its base branch.
...
Flags:
      --dry-run        Only check whether the trail is mergeable; do not merge
      --trail string   Trail to merge (number, id, or branch; defaults to the current branch's trail)

Changes

• api/trail_types.go — TrailMergeabilityResponse, TrailMergeResponse.
• trail_cmd.go — newTrailMergeCmd, runTrailMerge, fetchTrailMergeability, mergeTrailByNumber, printTrailMergeability, describeMergeBlockers. Extracts a shared resolveTrailBySelector helper and refactors runTrailShow to use it (removing duplicate selector-resolution logic).
• trail_merge_cmd_test.go — tests for the API helpers (path/method, server-error surfacing, ok:false rejection, 422 gate-failure message), describeMergeBlockers across all gate states, and the summary output.

Testing

• mise run check (fmt + lint + unit + integration + e2e canary) passes.

🤖 Generated with Claude Code

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Note

Medium Risk
Merging changes remote git state via the server; the CLI gates on mergeability first and verifies ok:true, but mistaken merges in automation remain the main operational risk.

Overview
Adds entire trail merge, which merges a trail’s branch into its base via existing API routes (GET …/mergeability, POST …/merge). The command resolves the trail with --trail or the current branch, requires a trail number, always prints a readiness summary (approvals, CI, up-to-date), and refuses to merge with ordered blocker messages when not mergeable. --dry-run stops after the check (non-zero exit when blocked, suitable for CI). Successful merges require the server’s ok: true before reporting the merge commit SHA, matching deleteTrailByNumber.

New API types TrailMergeabilityResponse and TrailMergeResponse decode those endpoints. resolveTrailBySelector is extracted from runTrailShow for shared lookup. trail_merge_cmd_test.go covers HTTP helpers, blocker text, and summary output.

^{Reviewed by Cursor Bugbot for commit 0b76faf. Configure here.}

[Copilot]

Pull request overview

Adds a new entire trail merge subcommand that checks a trail’s mergeability (approvals, CI checks, and base-branch freshness) and, when eligible, triggers a server-side merge; supports --dry-run to report mergeability without performing the merge.

Changes:

• Introduces entire trail merge command wiring and shared trail selector resolution (resolveTrailBySelector) in the trail command implementation.
• Adds API response types for mergeability and merge endpoints.
• Adds unit tests covering mergeability/merge API helpers and mergeability summary/blocker rendering.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
cmd/entire/cli/trail_cmd.go	Adds trail merge command plus mergeability/merge helpers and factors selector resolution into resolveTrailBySelector.
cmd/entire/cli/api/trail_types.go	Adds TrailMergeabilityResponse and TrailMergeResponse API types.
cmd/entire/cli/trail_merge_cmd_test.go	Adds tests for merge API helpers, blocker ordering/text, and mergeability summary output.