feat: add GitSync pull system task

[chubes4]

Summary

• Adds a gitsync_pull Data Machine system task that delegates to the existing API-first GitSync::pull() primitive.
• Registers the task so scheduled or webhook-triggered flows can refresh GitSync bindings without shelling out to WP-CLI.
• Documents the system-task usage in the GitSync docs.

Verification

• php -l inc/Tasks/GitSyncPullTask.php
• git diff --check

AI assistance

• AI assistance: Yes
• Tool(s): OpenCode (GPT-5.5)
• Used for: Implemented the task wrapper and documentation based on Chris's requested docs publishing workflow; Chris remains responsible for review and testing.

[homeboy-ci]

Homeboy Results — data-machine-code

Lint

❌ lint — failed

• phpstan — 3 finding(s)
• Total: 3 finding(s)

ℹ️ Auto-fix: homeboy lint data-machine-code --path /home/runner/work/data-machine-code/data-machine-code --changed-since ca0546f --fix (or homeboy refactor data-machine-code --path /home/runner/work/data-machine-code/data-machine-code --changed-since ca0546f --from lint --write)
ℹ️ Some issues may require manual fixes
ℹ️ Full options: homeboy docs commands/lint
ℹ️ Save lint baseline: homeboy lint data-machine-code --baseline
Deep dive: homeboy lint data-machine-code --changed-since ca0546f

Test

✅ test — passed

ℹ️ No impacted tests found for --changed-since ca0546f
ℹ️ Run full suite if needed: homeboy test data-machine-code
Deep dive: homeboy test data-machine-code --changed-since ca0546f

Audit

✅ audit — passed

• test_coverage — 1 finding(s)
• Total: 1 finding(s)

Deep dive: homeboy audit data-machine-code --changed-since ca0546f

Tooling versions

• Homeboy CLI: homeboy 0.189.0+fb8db38
• Extension: wordpress from https://github.com/Extra-Chill/homeboy-extensions
• Extension revision: 8541a487
• Action: unknown@unknown