Add -m shorthand for --manifest-path (#16858)

### What does this PR try to resolve?

* Solves #16726

### How to test and review this PR?

* In cases where you would expect `--manifest-path` to work, try `-m`
instead.

---

### Notes

* First time contributing to `cargo` so please let me know what I can do
to bring this PR up to par if I've missed anything!
* No AI tooling of any kind was used in the creation of this PR.

Author: weihanglo

src/cargo/util/command_prelude.rs

@@ -375,6 +375,7 @@ pub trait CommandExt: Sized {
     fn arg_manifest_path_without_unsupported_path_tip(self) -> Self {
         self._arg(
             opt("manifest-path", "Path to Cargo.toml")
+                .short('m')
                 .value_name("PATH")
                 .help_heading(heading::MANIFEST_OPTIONS)
                 .add(clap_complete::engine::ArgValueCompleter::new(

tests/testsuite/build.rs

@@ -293,6 +293,19 @@ For more information, try '--help'.
         .run();
 }
 
+#[cargo_test]
+fn cargo_compile_with_manifest_path_shorthand() {
+    let p = project()
+        .file("Cargo.toml", &basic_bin_manifest("foo"))
+        .file("src/foo.rs", &main_file(r#""i am foo""#, &[]))
+        .build();
+
+    p.cargo("build -m foo/Cargo.toml")
+        .cwd(p.root().parent().unwrap())
+        .run();
+    assert!(p.bin("foo").is_file());
+}
+
 #[cargo_test]
 fn chdir_gated() {
     let p = project()