Statically link WebView2Loader - single exe, no DLL needed

build.rs swaps the dynamic import library with the static archive
from webview2-com-sys, so the WebView2 loader code is baked into
the exe. msvc_compat.rs provides the MSVC CRT symbols (security
cookie, thread-safe init, C++ operators) that the MSVC-compiled
static library expects.

src-tauri/build.rs

@@ -7,5 +7,75 @@ fn main() {
         std::env::set_var("PATH", mingw_bin);
     }
 
+    // On GNU targets, replace the WebView2Loader import library with the static
+    // library so the loader is baked into the exe — no DLL to ship.
+    #[cfg(target_env = "gnu")]
+    swap_webview2_to_static();
+
     tauri_build::build()
 }
+
+/// Replace `WebView2Loader.dll.lib` (dynamic import lib) with the contents of
+/// `WebView2LoaderStatic.lib` (static archive) in the webview2-com-sys build
+/// output. The linker then statically links the WebView2 loader code, removing
+/// the runtime dependency on WebView2Loader.dll.
+#[cfg(target_env = "gnu")]
+fn swap_webview2_to_static() {
+    use std::fs;
+    use std::path::PathBuf;
+
+    let out_dir = std::env::var("OUT_DIR").unwrap_or_default();
+    // OUT_DIR = target/.../build/core-cooldown-HASH/out
+    // We need:  target/.../build/  (two levels up)
+    let build_dir = PathBuf::from(&out_dir)
+        .parent()   // core-cooldown-HASH
+        .and_then(|p| p.parent()) // build/
+        .map(|p| p.to_path_buf());
+
+    let build_dir = match build_dir {
+        Some(d) => d,
+        None => return,
+    };
+
+    let target_arch = match std::env::var("CARGO_CFG_TARGET_ARCH")
+        .unwrap_or_default()
+        .as_str()
+    {
+        "x86_64" => "x64",
+        "x86" => "x86",
+        "aarch64" => "arm64",
+        _ => return,
+    };
+
+    let entries = match fs::read_dir(&build_dir) {
+        Ok(e) => e,
+        Err(_) => return,
+    };
+
+    for entry in entries.flatten() {
+        let name = entry.file_name();
+        let name = name.to_string_lossy();
+        if !name.starts_with("webview2-com-sys-") {
+            continue;
+        }
+
+        let lib_dir = entry.path().join("out").join(target_arch);
+        let import_lib = lib_dir.join("WebView2Loader.dll.lib");
+        let static_lib = lib_dir.join("WebView2LoaderStatic.lib");
+
+        if static_lib.exists() && import_lib.exists() {
+            if let Ok(static_bytes) = fs::read(&static_lib) {
+                match fs::write(&import_lib, &static_bytes) {
+                    Ok(_) => println!(
+                        "cargo:warning=Swapped WebView2Loader to static linking ({})",
+                        lib_dir.display()
+                    ),
+                    Err(e) => println!(
+                        "cargo:warning=Failed to swap WebView2Loader lib: {}",
+                        e
+                    ),
+                }
+            }
+        }
+    }
+}