Claude/ephapax linear types e00 zs (#4)

* feat: Initial Ephapax language implementation

Ephapax is a linear type system for safe memory management
targeting WebAssembly.

This commit includes:

Core Implementation:
- ephapax-syntax: AST definitions with linear type annotations
- ephapax-typing: Linear type checker with region support
- ephapax-wasm: WASM code generator with bump allocation
- ephapax-runtime: no_std WASM runtime with region management

Formal Semantics (Coq):
- Syntax.v: Core type and expression definitions
- Typing.v: Linear typing rules with context tracking
- Semantics.v: Operational semantics and safety theorems

Documentation:
- Language specification (spec/SPEC.md)
- Comprehensive wiki documentation
- ROADMAP.md with detailed development plan
- CONTRIBUTING.adoc guide

Infrastructure:
- Cargo workspace with 4 crates
- CI/CD workflow for Rust and Coq
- EUPL-1.2 license

Key features:
- Linear types prevent use-after-free and memory leaks
- Region-based memory management for bulk deallocation
- Second-class borrows for temporary access
- Formal proofs in Coq for type safety

* feat(frontend): Add lexer and parser for Ephapax language

Implements Phase 2 (Language Frontend) of the Ephapax roadmap:

- ephapax-lexer: High-performance lexer using logos
  - Tokenizes all Ephapax syntax (keywords, operators, literals)
  - Support for nested block comments {- -}
  - String escape sequence handling
  - Comprehensive error recovery
  - 20+ unit tests

- ephapax-parser: Parser combinator implementation using chumsky
  - Complete expression parsing (let, fn, if, region, case, etc.)
  - Type parsing (base types, String@region, functions, products, sums)
  - Declaration parsing (fn, type)
  - Rich error reporting with ariadne
  - 19 unit tests + doc tests

All tests pass successfully.

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: hyperpolymath

src/ephapax-lexer/Cargo.toml

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: EUPL-1.2
+# SPDX-FileCopyrightText: 2025 Jonathan D.A. Jewell
+
+[package]
+name = "ephapax-lexer"
+description = "Lexer for the Ephapax programming language"
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+authors.workspace = true
+repository.workspace = true
+keywords.workspace = true
+categories.workspace = true
+
+[dependencies]
+logos = { workspace = true }
+smol_str = { workspace = true }
+thiserror = { workspace = true }
+
+[dev-dependencies]