feat: add WebAssembly support and fugue-evo-wasm bindings crate

- Add cargo feature flags: std, parallel, checkpoint (default all enabled)
- Feature-gate parallel/rayon functionality for WASM compatibility
- Make CheckpointError WASM-compatible with cfg-gated variants
- Add non-parallel impl blocks to SimpleGA for WASM target
- Feature-gate island model (requires parallel feature)
- Feature-gate checkpoint file I/O (requires checkpoint feature)
- Add to_json/from_json methods to InteractiveSession for WASM
- Create fugue-evo-wasm crate with JavaScript-friendly wrappers
- Add RealVectorOptimizer for browser-based optimization
- Support built-in fitness functions (Sphere, Rastrigin, Rosenbrock)
- Generate TypeScript definitions via wasm-pack build

Author: claude

Cargo.lock

@@ -1,3 +1,6 @@
+[workspace]
+members = [".", "crates/fugue-evo-wasm"]
+
 [package]
 name = "fugue-evo"
 version = "0.1.0"
@@ -9,6 +12,12 @@ repository = "https://github.com/alexnodeland/fugue-evo"
 keywords = ["genetic-algorithm", "evolution", "optimization", "probabilistic-programming"]
 categories = ["algorithms", "science"]
 
+[features]
+default = ["std", "parallel", "checkpoint"]
+std = []
+parallel = ["rayon"]
+checkpoint = []  # File-based checkpointing (requires std)
+
 [dependencies]
 # Linear algebra for CMA-ES
 nalgebra = "0.33"
@@ -17,27 +26,33 @@ nalgebra = "0.33"
 rand = "0.8"
 rand_distr = "0.4"
 
-# Parallelism
-rayon = "1.10"
+# Parallelism (optional)
+rayon = { version = "1.10", optional = true }
 
 # Serialization
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 bincode = "1.3"
 
-# Compression for checkpoints
-zstd = "0.13"
-
 # Error handling
 thiserror = "2.0"
 
 # Observability
 tracing = "0.1"
 fugue-ppl = "0.1.0"
 
+# WASM support (enabled via getrandom js feature when targeting wasm32)
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+getrandom = { version = "0.2", features = ["js"] }
+
 [dev-dependencies]
 # Testing utilities
 proptest = "1.5"
 criterion = "0.5"
 approx = "0.5"
 tempfile = "3.10"
+
+# Examples requiring parallel feature
+[[example]]
+name = "island_model"
+required-features = ["parallel"]

Cargo.toml

@@ -0,0 +1,41 @@
+[package]
+name = "fugue-evo-wasm"
+version = "0.1.0"
+edition = "2021"
+authors = ["Alex Nodeland"]
+description = "WebAssembly bindings for fugue-evo genetic algorithm library"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/alexnodeland/fugue-evo"
+keywords = ["genetic-algorithm", "wasm", "webassembly", "optimization"]
+categories = ["algorithms", "wasm"]
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[dependencies]
+# Core library without parallel/checkpoint features
+fugue-evo = { path = "../..", default-features = false, features = ["std"] }
+
+# WASM bindings
+wasm-bindgen = "0.2"
+wasm-bindgen-futures = "0.4"
+js-sys = "0.3"
+serde-wasm-bindgen = "0.6"
+
+# Serialization for JS interop
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+
+# Random number generation with JS entropy
+getrandom = { version = "0.2", features = ["js"] }
+rand = "0.8"
+
+[dev-dependencies]
+wasm-bindgen-test = "0.3"
+
+[profile.release]
+opt-level = "s"
+lto = true
+
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = false