fix: don't save lockfile if --frozen-lockfile

CONTRIBUTING.md

@@ -67,7 +67,7 @@ $ wget https://apt.llvm.org/llvm.sh -O - | sudo bash -s -- 18 all
 ```
 
 ```bash#Arch
-$ sudo pacman -S llvm clang lld
+$ sudo pacman -S llvm clang-18 lld
 ```
 
 ```bash#Fedora
@@ -86,6 +86,8 @@ Make sure Clang/LLVM 18 is in your path:
 
 ```bash
 $ which clang-18
+# if no clang-18, verify clang version instead
+$ clang --version
 ```
 
 If not, run this to manually add it:
@@ -100,7 +102,7 @@ $ export PATH="$(brew --prefix llvm@18)/bin:$PATH"
 
 ```bash#Arch
 # use fish_add_path if you're using fish
-$ export PATH="$PATH:/usr/lib/llvm18/bin"
+$ export PATH="/usr/lib/llvm18/bin:$PATH"
 ```
 
 {% /codetabs %}

src/install/install.zig

@@ -15439,6 +15439,9 @@ pub const PackageManager = struct {
         packages_len_before_install: usize,
         log_level: Options.LogLevel,
     ) OOM!void {
+        if (!this.options.do.save_lockfile) {
+          return;
+        }
         if (this.lockfile.isEmpty()) {
             if (!this.options.dry_run) delete: {
                 const delete_format = switch (load_result.*) {