Explore the mesh-llm source code in this repo (crates/mesh-llm/src/). Give me a summary of:

1. How many Rust source files are there and what does each one do? (one line per file)
2. What is the approximate total lines of code?
3. What external crates does it depend on? (check Cargo.toml)
4. What's the most complex file and why?

Don't read every file line by line — use bash tools (wc, grep, head) to be efficient.
