: regualar rlib, not a python extension module

Summary:
convert `monarch_hyperactor` from `rust_python_library` to `rust_library` and add `extension-module` to `monarch_extension`

`monarch_hyperactor` is not a Python extension module - it has no `#[pymodule]` entry point. the actual Python extension is `monarch_extension`, which depends on `monarch_hyperactor` and exposes its types to Python.

this change converts `monarch_hyperactor` from `rust_python_library` to `rust_library`, removing the `dependencies_override`. it adds the `extension-module` feature to pyo3 in `monarch_extension` where it belongs, removes a non-functional `#[pymodule]` attribute from `monarch_hyperactor/src/channel.rs`, and removes incorrect dependencies from Python type stubs that were depending on `monarch_hyperactor` instead of `monarch_extension`.

Differential Revision: D89247451

Author: shayne-fletcher

monarch_extension/Cargo.toml

@@ -30,7 +30,7 @@ monarch_rdma_extension = { version = "0.0.0", path = "../monarch_rdma/extension"
 monarch_tensor_worker = { version = "0.0.0", path = "../monarch_tensor_worker", optional = true }
 nccl-sys = { path = "../nccl-sys", optional = true }
 ndslice = { version = "0.0.0", path = "../ndslice" }
-pyo3 = { version = "0.24", features = ["anyhow", "multiple-pymethods", "py-clone"] }
+pyo3 = { version = "0.24", features = ["anyhow", "extension-module", "multiple-pymethods"] }
 rdmaxcel-sys = { path = "../rdmaxcel-sys", optional = true }
 serde = { version = "1.0.219", features = ["derive", "rc"] }
 tokio = { version = "1.47.1", features = ["full", "test-util", "tracing"] }

monarch_hyperactor/Cargo.toml

@@ -46,7 +46,7 @@ ndslice = { version = "0.0.0", path = "../ndslice" }
 nix = { version = "0.30.1", features = ["dir", "event", "hostname", "inotify", "ioctl", "mman", "mount", "net", "poll", "ptrace", "reboot", "resource", "sched", "signal", "term", "time", "user", "zerocopy"] }
 once_cell = "1.21"
 opentelemetry = "0.29"
-pyo3 = { version = "0.24", features = ["anyhow", "multiple-pymethods"] }
+pyo3 = { version = "0.24", features = ["anyhow", "multiple-pymethods", "py-clone"] }
 pyo3-async-runtimes = { version = "0.24", features = ["attributes", "tokio-runtime"] }
 serde = { version = "1.0.219", features = ["derive", "rc"] }
 serde_bytes = "0.11"

monarch_hyperactor/src/channel.rs

@@ -146,7 +146,6 @@ impl From<PyChannelTransport> for ChannelTransport {
     }
 }
 
-#[pymodule]
 pub fn register_python_bindings(hyperactor_mod: &Bound<'_, PyModule>) -> PyResult<()> {
     hyperactor_mod.add_class::<PyChannelTransport>()?;
     hyperactor_mod.add_class::<PyChannelAddr>()?;