Auto merge of #23300 - jdm:helpful-ml, r=asajeffrey

Magic Leap developer ergonomic improvements

These changes allow passing in command line arguments for Servo via a SERVO_ARGS from the mldb terminal when launching the activity, as well as passing in a launch URL as an argument. It also redirects stdout to the ML log, which allows observing the built-in profiler output.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #23041
- [x] These changes do not require tests because no magic leap testing.

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Cargo.lock

@@ -2437,6 +2437,7 @@ dependencies = [
 name = "libmlservo"
 version = "0.0.1"
 dependencies = [
+ "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
  "libservo 0.0.1",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "servo-egl 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -4178,7 +4179,6 @@ dependencies = [
  "libloading 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libservo 0.0.1",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_json 1.0.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -4202,6 +4202,7 @@ dependencies = [
  "jni 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.13 (registry+https://github.com/rust-lang/crates.io-index)",
  "simpleservo 0.0.1",
 ]