feat: add infer and tree_magic_mini meta plugins, make zstd internal by default

- Add infer crate as meta plugin for MIME type detection
- Add tree_magic_mini crate as alternative meta plugin for MIME type detection
- Add zstd, infer, tree_magic_mini to default features
- Fix static build script to use musl target instead of glibc+crt-static
- Remove hardcoded shell list from --generate-completion help text
- Fix update() in both new plugins to emit MIME metadata when buffer fills

src/compression_engine/program.rs

@@ -1,4 +1,4 @@
-use anyhow::{anyhow, Context, Result};
+use anyhow::{Context, Result, anyhow};
 use log::*;
 use std::fs::File;
 use std::io::{Read, Write};