Add a final summary to dev-tools sync

[coisa]

Objective

Improve dev-tools:sync output so maintainers can see a concise summary of what changed, what was skipped, and what needs attention.

Current Limitation

dev-tools:sync orchestrates several commands, but its final output does not provide a single actionable summary across phases such as Composer metadata, workflow stubs, .editorconfig, Dependabot, wiki, .gitignore, .gitattributes, skills, license, and Git hooks.

Proposed Work

Add a final sync summary that aggregates each phase result into deterministic, human-readable output.

Scope

• Report changed, created, skipped, repaired, and no-op phases.
• Include file paths or resource names when practical.
• Keep output stable enough for tests and CI logs.
• Preserve current command behavior and exit codes unless a real failure occurs.
• Add tests for mixed changed/skipped/no-op sync results.

Non-goals

• Changing the sync phases themselves.
• Adding dry-run or check behavior; that belongs to a separate issue.
• Introducing machine-readable output in the first implementation.

Acceptance Criteria

Delivery Criteria

• dev-tools:sync prints a final summary after all queued sync phases complete.
• The summary distinguishes changed, skipped, repaired, and unchanged phases.
• The summary includes affected paths for file-based operations where available.
• Existing phase output remains useful and is not replaced by vague aggregate text.
• Tests cover a sync run with at least one changed phase and one skipped/no-op phase.

Architectural / Isolation Criteria

• Summary collection is isolated from command orchestration where practical.
• SyncCommand remains focused on sequencing sync phases.
• Output is deterministic and suitable for assertions.