Preserve user-managed /usr/local/bin/code in RPM %post scriptlet

[yogeshwaran-c]

What this PR does

The RPM %post scriptlet currently removes /usr/local/bin/code unconditionally on every install/upgrade of the stable code package:

%post
# Remove the legacy bin command if this is the stable build
if [ "%{name}" = "code" ]; then
    rm -f /usr/local/bin/code
fi

/usr/local/bin/code is not a path owned by this package, and it's a common place for users to drop a wrapper script (for example, to launch /usr/bin/code with extra flags like --ozone-platform=wayland system-wide). Deleting it on every RPM upgrade silently destroys user-managed files.

This PR keeps the legacy cleanup, but only when the file is a symlink pointing at the target the package itself used to install (/usr/share/code/bin/code / %{_datadir}/%{name}/bin/%{name}). Regular files (user wrapper scripts) and symlinks to other targets are left untouched.

Behavior change

• Before: rm -f /usr/local/bin/code ran on every %post, removing whatever was at that path.
• After: removal happens only when /usr/local/bin/code is a symlink whose target is the legacy package-installed location.

This preserves the original intent (cleaning up the legacy symlink from very old packages) without trampling files the user owns.

Testing notes

This affects RPM packaging only and is exercised at install time. Manual verification scenarios:

1. A regular file at /usr/local/bin/code (e.g. a wrapper shell script) -> preserved across RPM upgrade.
2. A symlink at /usr/local/bin/code -> /some/user/path/code -> preserved across RPM upgrade.
3. A symlink at /usr/local/bin/code -> /usr/share/code/bin/code (legacy package layout) -> removed, matching previous cleanup behavior.
4. No file at /usr/local/bin/code -> no-op.

Fixes #236132

[vs-code-engineering]

📬 CODENOTIFY

The following users are being notified based on files changed in this PR:

@rzhao271

Matched files:

• resources/linux/rpm/code.spec.template