Fix: Expand Swift variadic functions into explicit Java overloads

[amanmaurya92]

Fixes #830.

Description

This PR introduces support for generating Java bindings for Swift variadic functions. Previously, variadic functions were not handled correctly in the generated Java code.

Changes Made

• Variadic Expansion: Added a mechanism to expand variadic Swift functions (e.g., func log(items: String...)) into multiple explicit Java overloads up to a configurable limit (effectiveMaxVariadicOverloads).
• Immutability Maintained: Refactored FFMSwift2JavaGenerator and JNISwift2JavaGenerator to perform the overload expansion using a local variable during initialization. This keeps analysis as an immutable let property on the generator classes, addressing previous review feedback.
• Initialization Order Fix: Ensured that self.analysis is fully initialized before invoking instance methods like generateInterfaceWrappers() in JNISwift2JavaGenerator, resolving Swift compiler errors regarding premature use of self.

This ensures we get comprehensive Java bindings for variadic functions without sacrificing the immutability of the generator's internal state.

[ktoso]

Though I wonder it it would be better to support it by generating a number of overloads with up to N parameters where we take the N from configuration maybe?

[amanmaurya92]

Yeah, I like that approach. It seems like a much cleaner solution.
I'll update the PR to do that.

[ktoso]

Thanks!

[ktoso]

This is shaping up great, some comments still and please add runtime testing

[ktoso]

Please make a runtime test; we make those by adding a func in the Samples/SwiftJavaExtractJNISampleApp and exercise the functions in Java test code in the same project. This verifies it all works at runtime as well

[ktoso]

Thanks this is pretty good, we might want to move the expand... outside the initializer though, but we can do it in a follow up

[amanmaurya92]

Thanks! I'll fix the failing checks and update the PR.

[amanmaurya92]

I didn't expect to run into so many formatting issues. I'll get the formatter working locally before my next PR so I can catch these ahead of time.

[ktoso]

Hah yeah, sorry about this -- sadly the formatting can be pretty picky, definitely worth getting working locally

[ktoso]

I'll apply fixes, since I'm cutting a release now -- please look into getting formatter working locally though, it should mostly just work tbh 🤔

[ktoso]

Thanks again!