feat(template): add procurement approval agent (v0.6-compatible)

[VasuBansal7576]

Description

Adds a Hive v0.6-compatible Procurement Approval Agent template with adaptive routing and continuous processing support, while preserving the expected interactive approval workflow.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Documentation update

Related Issues

Fixes #4987

Changes Made

• Added complete procurement agent template under examples/templates/procurement_approval_agent/ including:
  • graph/nodes/config/CLI
  • monitoring + daemon support
  • demo scripts and deployment helpers
  • test suite
• Implemented adaptive QuickBooks routing:
  • API path when credentials are available
  • CSV fallback path when credentials are not available
• Added first-run setup flow and interactive checkpoints in monitor/run workflows.
• Added duplicate-request guard and reset/setup helper command.
• Added mockable QuickBooks sync flow and output artifact generation.
• Updated docs and usage examples for local testing and workflow demos.

Testing

Describe the tests you ran to verify your changes:

• Manual testing performed

Additional verification run for this PR:

• PYTHONPATH=core:examples/templates pytest -q examples/templates/procurement_approval_agent/tests (12 passed)
• PYTHONPATH=core:examples/templates python -m procurement_approval_agent validate
• PYTHONPATH=core:examples/templates python -m procurement_approval_agent info
• End-to-end CLI runs for both API-declared and CSV fallback paths in mock mode

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Demo Video

Demo recording: https://www.youtube.com/watch?v=wh2fun0sT48