Description of the change

Adds a codegen option that allows for opting out of the javy_source custom section. If -C source=n is specified to the CLI, source-compression has no effect.

Fixes #982

Why am I making this change?

Allows for smaller Wasm modules output by Javy in case the source code is not necesary. Through local testing I was able to shrink my Wasm modules by about one third.

Checklist

• I've updated the relevant CHANGELOG files if necessary. Changes to javy-cli, javy-plugin, and javy-plugin-processing do not require updating CHANGELOG files.
• I've updated the relevant crate versions if necessary. Versioning policy for library crates
• I've updated documentation including crate documentation if necessary.