axon-frontend 0.3.0

AXON compiler frontend — lexer, parser, AST, epistemic type system, type checker, IR generator, compile-time checker. Zero runtime dependencies (no tokio/axum/sqlx/reqwest); consumable by any tool that analyses AXON source without running it. v0.3.0 closes Fase 14 (lossless lexing): the lexer emits comment tokens (`LineComment`, `BlockComment`, `DocLineComment`, `DocBlockComment`, `InnerDocLineComment`, `InnerDocBlockComment`) and the parser materialises them as `Trivia` attached to every Declaration variant via `leading_trivia` / `trailing_trivia` fields — the API surface that powers `axon fmt`, axon-lsp's formatter and hover docstring rendering, and any rustdoc-style documentation generator. Back-compatible: existing callers see empty trivia tuples until they opt in. v0.2.0 added Fase 13 typed channels (channel/emit/publish/discover) + `channel_analysis` module for LSP integration.