feat: payroll run approval workflow, totals endpoint, and audit log

[rmak78]

Summary

• add payroll approval workflow progression:
• add payroll run totals API endpoint for earnings/deductions/employer cost/net totals
• add payroll audit log table migration for status transition trail
• update README status section with payroll workflow delivery note

Migration

Validation

⛅️ wrangler 4.68.1 (update available 4.69.0)
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Total Upload: 40.92 KiB / gzip: 5.94 KiB
Your Worker has access to the following bindings:
Binding Resource
env.openclaw_pos (openclaw_pos) D1 Database
env.APP_ENV ("dev") Environment Variable
env.API_WRITE_KEY ("change-me") Environment Variable

--dry-run: exiting now. ✅