ci(codeql): remove reusable workflow

[ArchonVII]

Summary

• Remove the reusable CodeQL workflow body.
• Remove the CodeQL example caller and catalog/handoff references.
• Keep dependency-review and Dependabot automation untouched.

Verification

• npm test

command: npm test
location: local
result: pass: 5 files / 77 tests
timestamp: 2026-06-02T12:43:12Z

• git diff --check plus CodeQL absence checks

command: git diff --check; Test-Path .github/workflows/codeql.yml; Test-Path examples/codeql.yml; rg codeql references
location: local
result: pass: diff check exited 0, CodeQL workflow/example absent, no CodeQL references in README/HANDOFF/.github/examples
timestamp: 2026-06-02T12:43:12Z

Verification Notes

npm test passed 5 files / 77 tests.

git diff --check exited 0.

.github/workflows/codeql.yml and examples/codeql.yml are absent.

rg -n -i --glob '!node_modules/**' --glob '!*.lock' 'codeql|github/codeql-action|security-events' README.md HANDOFF.md .github examples reported no CodeQL references.

Docs / Changelog

Updated README.md and HANDOFF.md to remove CodeQL from the workflow catalog and handoff notes.

Changelog entry not added: this removes an unused workflow service from the shared catalog and does not change package runtime behavior.

Linked Issue

Closes #42