Relax exact version pins to allow compatibility with mlx-swift-lm

[jcalderita]

Problem

Package.swift uses exact: version pins for all dependencies:

.package(url: "https://github.com/ml-explore/mlx-swift", exact: "0.30.2"),
.package(url: "https://github.com/mlalma/MisakiSwift", exact: "1.0.6"),
.package(url: "https://github.com/mlalma/MLXUtilsLibrary.git", exact: "0.0.6")

This makes it impossible to use KokoroSwift alongside other packages that depend on mlx-swift (e.g., mlx-swift-lm), because SPM cannot resolve exact: "0.30.2" and >= 0.30.3 at the same time.

This is the same category of issue as #26 — constraints in Package.swift that prevent KokoroSwift from being used as a dependency in projects with other MLX-based packages.

Suggested fix

Change exact: to from: for all dependencies:

.package(url: "https://github.com/ml-explore/mlx-swift", from: "0.30.2"),
.package(url: "https://github.com/mlalma/MisakiSwift", from: "1.0.6"),
.package(url: "https://github.com/mlalma/MLXUtilsLibrary.git", from: "0.0.6")

The same change would be needed in MisakiSwift's Package.swift as well.

This allows SPM to resolve a compatible version across all packages while still respecting semver lower bounds.

Context

I'm building a Swift CLI that uses mlx-swift-lm for LLM inference and would like to add Kokoro TTS. Currently the only workaround is forking both repos to relax the pins.