v0.5.0

Changelog

• 0d0753c feat: initial release of Aperture - intelligent multi-model LLM routing gateway
• b5e8f57 feat: production readiness — fallback chain, retry, cost wiring, new roadmap
• e561051 feat: rate limiter, docker-compose, groq+ollama tests
• 1f71a64 feat: v0.5 — real embeddings, training export, A/B testing
• b073e30 fix: prevent Go toolchain auto-download in CI
• b3fea7a fix: resolve CI lint failure
• 86cb4ea fix: resolve critical bugs from code review
• 1e5b494 fix: simplify CI test to avoid toolchain covdata error
• 1feecba fix: use Go 1.25 in CI to match modernc.org/libc requirement