Replace copy genrules with copy_file

[dzbarsky]

Summary

Replace copy-only genrule targets with bazel_skylib copy_file targets for:

• Bazel executable .exe aliases
• the builtins zip resource redirect
• the Starlark CPU profiler JNI library alias
• JNI header and native library aliases

Each target permits symlinking, so copy_file creates a declared symlink action instead of invoking an ambient cp executable through a shell. This PR contains no third-party patch or dependency update.

This focused change is extracted from #30121 for independent review.

Motivation

The existing genrule targets assume the execution environment provides cp and a compatible shell. That assumption fails when Bazel runs on Windows while actions execute remotely on Linux. The dedicated copy_file rule also states the operation directly and removes repeated command strings.

Build API Changes

No.

Validation

• buildifier -mode=check src/BUILD src/main/java/com/google/devtools/build/lib/bazel/rules/BUILD src/main/java/net/starlark/java/eval/BUILD src/main/native/BUILD
• bazel aquery confirmed the expected Symlink or ExecutableSymlink action, input, and output for all nine generated targets
• bazel build --jobs=2 //src/main/java/com/google/devtools/build/lib/bazel/rules:builtins_bzl_zip //src/main/java/net/starlark/java/eval:cpu_profiler_jni_darwin //src/main/native:copy_link_jni_header //src/main/native:copy_link_jni_md_header //src/main/native:mac-compat

Release Notes

RELNOTES: None