fix: clippy manual_let_else in build.rs + coverage failures

[noahgift]

Bug

CI lint fails with clippy::manual_let_else in crates/presentar-cli/build.rs:39. Coverage also fails due to compilation errors.

Five-Whys

1. Why does clippy fail? -D warnings promotes manual_let_else to error.
2. Why is the pattern flagged? match ... { Ok(s) => s, Err(_) => { return; } } should be let ... else { return; }.
3. Why now? Rust 1.93+ clippy added this lint to the default pedantic set.

Fix

Refactor build.rs:39-45 to use let...else:

let Ok(yaml) = std::fs::read_to_string(&binding_path) else {
    println!("cargo:rustc-env=CONTRACT_BINDING_SOURCE=none");
    return;
};

🤖 Generated with Claude Code