chore(release): prepare v0.1.0 — Cargo metadata, CHANGELOG, README polish

- Cargo.toml: add `repository`, `homepage`, `documentation`,
  `keywords`, `categories`, `authors`, and `rust-version = "1.85"`
  (the version that stabilized edition 2024).
- CHANGELOG.md: new file in Keep-a-Changelog format with the full
  v0.1.0 inventory (core, traits, pareto utilities, operators,
  algorithms, metrics, examples, and the `serde`/`parallel` features).
- README.md: add crates.io / docs.rs / license badges and a Changelog
  link.

Pre-release verification (all clean):
- cargo build (default + --features parallel)
- cargo test (default, parallel, serde, --all-features) — 111 lib +
  3 doc tests pass under each.
- cargo clippy --all-targets --all-features -- -D warnings
- cargo doc --no-deps
- cargo package --no-verify → 57 files, 261 KB

README.md

@@ -1,5 +1,9 @@
 # heuropt
 
+[![Crates.io](https://img.shields.io/crates/v/heuropt.svg)](https://crates.io/crates/heuropt)
+[![Documentation](https://docs.rs/heuropt/badge.svg)](https://docs.rs/heuropt)
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
+
 A practical Rust toolkit for implementing heuristic single-objective,
 multi-objective, and many-objective optimization algorithms.
 
@@ -136,4 +140,8 @@ See `docs/heuropt_tech_design_spec.md` for the full design rationale.
 
 ## License
 
-MIT.
+MIT — see [LICENSE](LICENSE).
+
+## Changelog
+
+See [CHANGELOG.md](CHANGELOG.md).