v0.15.0

This release adds support for Go 1.25 and drops support for Go 1.23 and Go 1.24.

Literal obfuscation is improved slightly so that deobfuscation via static analysis is not as easy to achieve.

Attempting to obfuscate packages which inject function headers into the runtime via //go:linkname now fails in a very clear way, as such packages like github.com/bytedance/sonic/loader cannot work with an obfuscated runtime.

A number of fixes are also included:

• Fix obfuscating packages whose Go files all import C
• Fix builds where GOROOT is a symbolic link
• Fix control flow obfuscation on packages importing unsafe
• Fix a regression where build flags were not obeyed in garble reverse