docs(governance): enforce linked issue policy

[srpatcha]

Summary

• add the canonical same-repository linked-issue workflow pinned to organization policy commit 92cb596c773496ec4df76717e8acf0e6b7700f73
• preserve and extend ebuild's existing agent guidance with repository-specific component boundaries and validation commands
• reconcile the existing pull request template, including repair of malformed control characters, while retaining its summary, change type, testing, checklist, logs, and notes sections
• version the six currently published ebuild Wiki pages under docs/wiki/

Validation

• python -c "import yaml, pathlib; ...": passed; workflow parsed and both policy references equal 92cb596c773496ec4df76717e8acf0e6b7700f73
• canonical workflow blob comparison after required SHA substitution: passed (973e19e043e049f08a278caf3bdfbeb4e6ef2584 for both files)
• published Wiki blob comparison: passed for all six files; docs/wiki/ contains exactly six files
• npx --yes markdownlint-cli2 --config C:\Users\spatchava\Desktop\task40-tooling-rollout\ebuild\markdownlint-rollout.jsonc AGENTS.md .github/PULL_REQUEST_TEMPLATE.md docs/wiki/*.md: passed, 8 files, 0 errors; disabled only line length, inline HTML, emphasis-as-heading, first-H1, table-style, and continued-numbering rules to preserve published Wiki text and existing template/agent structure
• git diff --cached --check: passed
• python -m pytest tests/unit/test_ci_gate.py tests/unit/test_documented_commands_exist.py -v --tb=short: 18 passed
• canonical policy tests at 92cb596c773496ec4df76717e8acf0e6b7700f73: 18 passed
• workspace diagnostics and change validation: no errors

Baseline blockers

• Full python -m pytest tests/ -q --tb=short: 9 failed, 664 passed, 8 skipped. All nine failures are in tests/unit/test_index_sync.py because PackageRecipe.to_dict is absent. The untouched 8b623d5786b5f841823f92a5506269f1e155a0f1 baseline reproduces the same nine failures (9 failed, 13 passed for that file).
• python -m ruff check .: four findings in unchanged test files (F811, W292, and two E402 findings). The untouched baseline reproduces the same four findings.
• yamllint is not installed in the environment; YAML was validated with PyYAML instead.

Fixes #129