refactor(shm)!: Extract one_way_shared_memory to IPC and prepare libdd-remote-config for python

datadog-ipc/Cargo.toml

@@ -68,3 +68,6 @@ unexpected_cfgs = { level = "warn", check-cfg = ['cfg(polyfill_glibc_memfd)'] }
 
 [features]
 tiny-bytes = ["libdd-tinybytes"]
+# Wake `OneWayShmReader::wait_for_change` via a futex on the generation word
+# (Linux only). Without this, the wait falls back to a timed poll.
+one_way_shm_futex = []

datadog-ipc/src/lib.rs

@@ -10,6 +10,7 @@
 pub mod example_interface;
 pub mod handles;
 
+pub mod one_way_shared_memory;
 pub mod platform;
 pub mod rate_limiter;
 pub mod shm_stats;