Consider pythonw when copying entrypoints in uv run (#15134)

## Summary

Follow up from
https://github.com/astral-sh/uv/pull/15068#discussion_r2258586926

It seems when copying entrypoints we're ignoring whether it was pythonw
vs not.

## Test Plan

Updated existing test.

crates/uv/src/commands/project/run.rs

@@ -1937,7 +1937,15 @@ fn copy_entrypoint(
         return Ok(());
     };
 
-    let launcher = launcher.with_python_path(python_executable.to_path_buf());
+    let is_gui = launcher.python_path.ends_with("pythonw.exe");
+
+    let python_path = if is_gui {
+        python_executable.with_file_name("pythonw.exe")
+    } else {
+        python_executable.to_path_buf()
+    };
+
+    let launcher = launcher.with_python_path(python_path);
     let mut file = fs_err::OpenOptions::new()
         .create_new(true)
         .write(true)

crates/uv/tests/it/run.rs

@@ -1344,6 +1344,9 @@ fn run_with_overlay_interpreter() -> Result<()> {
 
         [project.scripts]
         main = "foo:main"
+
+        [project.gui-scripts]
+        main_gui = "foo:main_gui"
         "#
     })?;
 
@@ -1362,10 +1365,19 @@ fn run_with_overlay_interpreter() -> Result<()> {
             base = Path(sys.executable)
             shutil.copyfile(base.with_name("main").with_suffix(base.suffix), sys.argv[1])
 
+        def copy_gui_entrypoint():
+            base = Path(sys.executable)
+            shutil.copyfile(base.with_name("main_gui").with_suffix(base.suffix), sys.argv[1])
+
         def main():
             show_python()
             if len(sys.argv) > 1:
                 copy_entrypoint()
+
+        def main_gui():
+            show_python()
+            if len(sys.argv) > 1:
+                copy_gui_entrypoint()
        "#
     })?;
 
@@ -1390,6 +1402,20 @@ fn run_with_overlay_interpreter() -> Result<()> {
      + iniconfig==2.0.0
     ");
 
+    // The project's gui entrypoint should be rewritten to use the overlay interpreter.
+    #[cfg(windows)]
+    uv_snapshot!(context.filters(), context.run().arg("--with").arg("iniconfig").arg("main_gui").arg(context.temp_dir.child("main_gui").as_os_str()), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    [CACHE_DIR]/builds-v0/[TMP]/pythonw
+
+    ----- stderr -----
+    Resolved 6 packages in [TIME]
+    Audited 4 packages in [TIME]
+    Resolved 1 package in [TIME]
+    ");
+
     #[cfg(unix)]
     insta::with_settings!({
         filters => context.filters(),
@@ -1439,9 +1465,26 @@ fn run_with_overlay_interpreter() -> Result<()> {
      + sniffio==1.3.1
     ");
 
+    // When layering the project on top (via `--with`), the overlay gui interpreter also should be used.
+    #[cfg(windows)]
+    uv_snapshot!(context.filters(), context.run().arg("--no-project").arg("--gui-script").arg("--with").arg(".").arg("main_gui"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    [CACHE_DIR]/builds-v0/[TMP]/pythonw
+
+    ----- stderr -----
+    Resolved 4 packages in [TIME]
+    ");
+
     // Switch to a relocatable virtual environment.
     context.venv().arg("--relocatable").assert().success();
 
+    // Cleanup previous shutil
+    fs_err::remove_file(context.temp_dir.child("main"))?;
+    #[cfg(windows)]
+    fs_err::remove_file(context.temp_dir.child("main_gui"))?;
+
     // The project's entrypoint should be rewritten to use the overlay interpreter.
     uv_snapshot!(context.filters(), context.run().arg("--with").arg("iniconfig").arg("main").arg(context.temp_dir.child("main").as_os_str()), @r"
     success: true
@@ -1455,6 +1498,20 @@ fn run_with_overlay_interpreter() -> Result<()> {
     Resolved 1 package in [TIME]
     ");
 
+    // The project's gui entrypoint should be rewritten to use the overlay interpreter.
+    #[cfg(windows)]
+    uv_snapshot!(context.filters(), context.run().arg("--with").arg("iniconfig").arg("main_gui").arg(context.temp_dir.child("main_gui").as_os_str()), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    [CACHE_DIR]/builds-v0/[TMP]/pythonw
+
+    ----- stderr -----
+    Resolved 6 packages in [TIME]
+    Audited 4 packages in [TIME]
+    Resolved 1 package in [TIME]
+    ");
+
     // The package, its dependencies, and the overlay dependencies should be available.
     context
         .run()
@@ -1498,6 +1555,18 @@ fn run_with_overlay_interpreter() -> Result<()> {
     Resolved 4 packages in [TIME]
     ");
 
+    // When layering the project on top (via `--with`), the overlay gui interpreter also should be used.
+    #[cfg(windows)]
+    uv_snapshot!(context.filters(), context.run().arg("--no-project").arg("--gui-script").arg("--with").arg(".").arg("main_gui"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    [CACHE_DIR]/builds-v0/[TMP]/pythonw
+
+    ----- stderr -----
+    Resolved 4 packages in [TIME]
+    ");
+
     Ok(())
 }