Fix capitalized Tool-Semantics repo URLs across docs and pyproject

[askmy-stack]

Summary

Several files link to `askmy-stack/Tool-Semantics` (mixed case). The canonical repo is `askmy-stack/tool-semantics`. Wrong casing breaks badges, PyPI project URLs, and Security Advisories links on case-sensitive consumers.

Acceptance criteria

• `pyproject.toml` `[project.urls]` use `askmy-stack/tool-semantics`
• README badges / good-first-issue links use lowercase path
• `SECURITY.md` advisory URL uses lowercase path
• `.github/ISSUE_TEMPLATE/config.yml` contact links updated
• Grep the repo for `Tool-Semantics` in URLs only and fix remaining hits

Why

OSS discoverability and correct GitHub Actions badge rendering.