Complete repository governance and maintenance

[daniel-techAI]

Summary

• add source-code licensing with an explicit personal-content and asset exclusion
• add contribution, support, private security-reporting, ownership, issue-form, and pull-request guidance
• configure weekly npm and GitHub Actions dependency updates
• replace the README's missing-license warning with the actual licensing boundary

Validation

• YAML issue forms and Dependabot configuration parsed successfully
• Markdown and YAML formatting checked
• git diff --check passed
• existing production quality workflow will run on this pull request

No portfolio content, runtime code, deployment behavior, or user-facing interaction is changed.