Implement the governed Git change-set workflow and repository fixture

Plan ID

EM-07

Purpose

Exercise the approved ears-manager behavior through the governed single-player Git workflow.

Scope

• Create change-set branches using the documented naming and base-commit rules.
• Stage only registered specification paths, manifests, project configuration, and manager-owned projection entries.
• Prepare deterministic commits and pull-request summaries from compare and impact.
• Reject direct specification edits, unregistered paths, forbidden branches, force pushes, and default-branch pushes.
• Implement the local bare-repository fixture covering initialization, proposal, refresh, merge, and registration evidence.

Dependencies

Depends on EM-05 and EM-06. The Git contract in #34 is complete.

Acceptance criteria

• The fixture demonstrates a complete initialize, propose, validate, branch, commit, refresh, and merge flow.
• Every failure leaves the repository unchanged or provides a deterministic retry path.
• Only explicitly owned paths are staged.
• Approved change-set manifests are immutable.
• The fixture proves registration is idempotent by change-set and merge commit.

Out of scope

WMS lifecycle transitions and Job Site execution remain outside this issue.

Start with the completed Git contract in #34 and review the dependencies on EM-05 and EM-06 before tracing the existing ears-manager entry points. Exercise the local bare-repository fixture through initialization, proposal, validation, branching, commit, refresh, and merge. Done means the acceptance criteria are demonstrated, including owned-path staging, immutable manifests, deterministic failures, and idempotent registration evidence.