docs: add shift handoff template appendix

[Hinotoi-agent]

Summary

• Adds an informative Shift Handoff Template appendix for APTS-HO-019 operational continuity.
• Links the template from the appendix index, Getting Started document map, and Human Oversight guidance.
• Captures pending approvals, active scope, kill-switch authority, safety signals, tool/connector state, and incoming-operator acceptance in a reviewable record.

Why

APTS-HO-019 already calls for structured shift handoff, stale approval expiry, suppression-rule review, and desensitization monitoring. This PR provides a lightweight implementation artifact that operators, vendors, and reviewers can adapt without adding new normative requirements.

Affected sections

• standard/appendix/Shift_Handoff_Template.md
• standard/README.md
• standard/Getting_Started.md
• standard/3_Human_Oversight/README.md
• standard/3_Human_Oversight/Implementation_Guide.md

Contributing.md checklist

• No overlapping open PR or issue was found for a dedicated shift handoff template.
• Affected sections are listed above.
• Formatting was checked with git diff --check.
• Touched relative Markdown links were verified locally.
• Markdown table validation and internal-link checks were run locally.
• AI assistance was used to draft and validate this documentation change.

Notes

This appendix is informative and does not create or modify APTS requirements.

[jinsonvarghese]

@Hinotoi-agent This covers the structured handoff, stale approval expiry, and suppression-rule review well. Two things to fix before merging:

1. Rebase needed - The branch predates PR docs: Add advisory requirement APTS-MR-A01 Goal Misgeneralization and Emergent Misalignment Evaluation Suite #43, so the advisory count in standard/README.md and standard/Getting_Started.md is reverting from 14 back to 13. Rebase against current main to pick up the correct count.
2. Desensitization monitoring - HO-019 has four governance areas. The template covers three but has no section for desensitization monitoring (tracking operator response times and alert acknowledgment rates to detect performance degradation). A small table or checklist item capturing response time trends and alert fatigue indicators for the outgoing shift would close this gap.

[Hinotoi-agent]

Thanks for the review. I addressed both items in commit b599963.

What changed:

• Rebasing the branch onto current main preserved the updated advisory count of 14 in standard/README.md and standard/Getting_Started.md.
• Added a dedicated Desensitization Monitoring section to standard/appendix/Shift_Handoff_Template.md with response-time trends, alert acknowledgment rates, alert-fatigue indicators, and suppression-pressure tracking for the outgoing shift.
• Added the same desensitization review signal to the incoming-operator checklist and reviewer questions.

Validation:

• git diff --check upstream/main...HEAD passed.
• uv run ruff check . passed.
• python scripts/validate_yaml.py passed.
• python scripts/validate_markdown_tables.py passed.
• python scripts/check_internal_markdown_links.py passed.
• python scripts/check_generated_artifacts.py passed.
• Targeted touched-file Markdown link check passed.
• Verified standard/README.md and standard/Getting_Started.md both retain the 14-advisory count.
• uv run pytest -q returned no tests collected, which is expected for this docs-only change.
• GitHub Repository sanity checks passed on the pushed head.