fix: align TypeScript types with native bindings

[maxgalbu]

Summary

Four places where the published TypeScript types disagree with the library's own native (C++/JSI) argument parsing. Each fix is verified against the repo's own native source on main; these were not runtime-tested on a device.

1. Mat.create — required params typed as optional (segfault)

• Native: cpp/structures/mat/MatFactory.cpp:13-15 reads args[0].asNumber(), args[1].asNumber(), args[2].asNumber() unconditionally (the data argument is guarded by count > 3 at line 21, but rows/cols/type are not).
• Current TS: static create(rows?: number, cols?: number, dataType?: DataTypes, data?: number[]) in src/objects/Objects.ts.
• Symptom: the optional typing invites Mat.create() with fewer than 3 args, which reads non-existent JSI arguments and segfaults.
• Fix: make rows, cols, dataType required; keep data? optional.

2. getPerspectiveTransform — wrong vector type

• Native: cpp/FOCV_Function.cpp:1221-1222 reads args.asPoint2fVectorPtr(1) / asPoint2fVectorPtr(2) for src and dst.
• Current TS: src/dst typed as PointVector in src/functions/ImageProcessing/ImageTransform.ts.
• Symptom: passing a PointVector throws Argument is not a Point2fVector at runtime.
• Fix: type src/dst as Point2fVector and update the type import.

3. Mat.saveToFile — missing params

• Native: cpp/structures/mat/MatDelegate.cpp reads path = args[0] (string, line 100), format = args[1] (string, must be "jpeg" or "png", line 107), compression = args[2] (number 0..1, line 110).
• Current TS: saveToFile(path: string): void in src/objects/Objects.ts.
• Symptom: the type omits two required arguments, so type-checked calls pass only path and fail native validation.
• Fix: saveToFile(path: string, format: 'jpeg' | 'png', compression: number): void.

4. saveToFile native arg-count guard is off by one

• Native: cpp/structures/mat/MatDelegate.cpp:93 guards with if (count < 4) but the handler only reads args[0..2] (3 args).
• Symptom: a correct 3-argument call throws saveToFile requires 3 arguments: path, format, compression.
• Fix: change the guard to if (count < 3).

Verification

Verified against the repo's native source (not runtime-tested). yarn typecheck and yarn lint pass locally; the lefthook pre-commit hook (types, lint, commitlint) passed on commit.