feat: support stream

[kerthcet]

What this PR does / why we need it

Which issue(s) this PR fixes

Fixes #

Special notes for your reviewer

Does this PR introduce a user-facing change?

[kerthcet]

/kind feature

[Copilot]

Pull request overview

This PR introduces a first-class Stream abstraction to the safe mlx crate API and wires stream selection into common array operations, enabling explicit CPU/GPU scheduling while keeping operator ergonomics via the default stream.

Changes:

• Add a safe Stream wrapper with CPU/GPU constructors, Default, and set_as_default.
• Extend Array with eval + scalar/vec extraction helpers and add stream-aware arithmetic/unary/reduction ops.
• Add operator overloads that run on the current default stream; update the hello example accordingly.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
crates/mlx/src/stream.rs	Introduces Stream wrapper + default-stream management API.
crates/mlx/src/lib.rs	Exposes Stream from the crate root.
crates/mlx/src/dtype.rs	Extends ArrayElement to support typed scalar reads and typed data pointers.
crates/mlx/src/array.rs	Adds stream-aware ops, evaluation helpers, and operator overloads using the default stream.
crates/mlx/examples/hello.rs	Demonstrates default-stream behavior and per-op explicit stream control.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 7 comments.

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (2)

crates/mlxcore-sys/build.rs:17

• The panic message says "macOS on Apple Silicon", but the guard only checks target_os = "macos". Building on macOS x86_64 will proceed until later failures. Prefer checking target_arch = "aarch64" too so the early error matches the supported platform.
  README.md:39
• cargo run --example hello won't work from a virtual workspace root (this repo's root Cargo.toml has no [package]). You need to specify the package that owns the example, otherwise Cargo errors due to missing default package selection.

Runnable examples live in `crates/mlxcore/examples`:

```sh
cargo run --example hello

</details>

[Copilot]

Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (2)

crates/mlxcore-sys/build.rs:17

• The platform guard only checks target_os = "macos", but the panic message claims Apple Silicon only. Either enforce target_arch = "aarch64" as well, or adjust the message so it matches what the code actually checks.
  crates/mlxcore/src/lib.rs:2
• This intra-doc link likely won’t resolve because Cargo crate names use hyphens (mlxcore-sys), but Rust paths/intra-doc links use underscores (mlxcore_sys). Use the Rust crate identifier in the link target.

[kerthcet]

/lgtm

[InftyAI-Agent]

Approved: PR has both lgtm and approved labels