Lazy For() Comprehension Generator

[pivovarit]

Introduces a generator for lazy for-comprehension variants that produce intermediate ForLazyN<M> classes for supported monadic types (e.g., Option, Try, Either, etc.).

This addition complements the existing eager for-comprehension generator by introducing a lazy variant.

• Added generation of ForLazyN<M> classes (arity 2 to N) that:
  • Use one monadic source (ts1) followed by a chain of dependent functions (ts2, ts3, …).
  • Allow lazy composition of monadic operations through nested lambdas.
• Added corresponding For(...) factory methods for convenient construction.
• Implemented a recursively generated yield(...) method with proper indentation and block structure for readability.

The generator handles mixed monadic/function parameter patterns such as:

Option<T1> ts1;
Function1<T1, Option<T2>> ts2;
Function2<T1, T2, Option<T3>> ts3;

expands for-comprehension with lazily-evaluated variants, so that the existing is possible:

Option<Integer> result = API.For(
  calculate1(),
  r1 -> calculate2(r1),
  (r1, r2) -> calculate3(r1, r2)).yield((r1, r2, r3) -> r1 + r2 + r3);

The generator enforces that the first argument is always a monadic value, not a function. This is necessary because:

• The first argument acts as the entry point of the comprehension; it provides the initial context for all later flatMap calls.
• If ts1 were also a function (e.g., Function0<M<T1>>), Java’s generic type inference fails to resolve chained type variables properly.
• Subsequent arguments can safely be functions (FunctionN<T1, ..., TN, M<T(N+1)>>), since their input types are already determined by previous monadic values.

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related: #3038