fix: import escaped server.properties from distributed worlds

[cotore-game]

Changes

• Accept Java Properties escapes (including \: and \uXXXX) and continuation lines in imported server.properties.
• Normalize distributed level-name to the managed data/world layout rather than rejecting the import.
• Add regression coverage for the supplied Fantasia Arena properties and malformed escapes; clarify behavior in both READMEs.
• Refresh the version-check dashboard test fixture for the current release.

Verification

• The supplied Fantasia Arena server.properties validates successfully.
• bash tests/run-tests.sh: 146 passed, 1 skipped (zip unavailable in local environment).
• bash -n tests/run-tests.sh and git diff --check pass.

This PR does not change or import any files in the existing server instance.