fix: support colon separator in Quill references

[nibsbin]

Summary

This PR fixes an issue where Quill references using a colon () separator (e.g., usaf_memo:0.1) were incorrectly parsed as invalid names.

Changes

• Modified crates/core/src/version.rs to support both @ and : as name/version separators.
• Added unit tests in version.rs to validate colon-separated references.
• Added integration tests in crates/quillmark/tests/versioning_test.rs to ensure end-to-end resolution works for both syntaxes.

Impact

Resolves WASM rendering errors where external references or manual overrides used the colon syntax standard in some environments.