chore: use public repository metadata

[YfengJ]

Summary

• update the package repository URL from git:// to git+https://
• leave runtime code, dependencies, package version, entry points, types, license, and package contents unchanged

Validation

• npm view toml --json
• metadata assertion for package identity, entry points, types, license, and repository fields
• npm ci --ignore-scripts --no-audit --no-fund
• npm run build
• npm test
• npm pack --dry-run --ignore-scripts --json .
• git diff --check

Note: npm run test:spec currently requires the external .binarymuse/toml-test fixture checkout and cannot run from a fresh clone without that data.

[YfengJ]

CI note: the failing Node 24 job appears unrelated to this metadata-only change. I reproduced the same npm run test:spec result on upstream master (3840fac) and on this branch: both fail only on the current external toml-test BOM cases, valid/utf8-bom-01 and valid/utf8-bom-02. The package local npm test suite passes, and this PR only changes the repository URL metadata.