Implement optimization for Primitive lists

[Shibi-bala]

Before this PR

Conjure holds primitive arrays as boxed lists. Instead, we can switch to primitive array lists that are backed by primitive typed arrays (double[]) rather than lists (ArrayList).

After this PR

==COMMIT_MSG== ==COMMIT_MSG==

Possible downsides?

[changelog-app[bot]]

Generate changelog in changelog-dir>`changelog/@unreleased`</changelog-dir

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Type

- [ ] Feature - [ ] Improvement - [ ] Fix - [ ] Break - [ ] Deprecation - [ ] Manual task - [ ] Migration

Description

Implement optimization for Primitive lists **Check the box to generate changelog(s)** - [ ] Generate changelog entry

[carterkozak]

In terms of sequencing, I think we should split this up into a few parts:

1) new generic list factory methods ConjureCollections which do not allow null values + update codegen to use them. note that list<any> should perhaps be allowed to contain null, as List.of(Optional.empty()) serializes to [null] which deserializes as an array containing null. 2) new specialized list factory methods for primitives in ConjureCollections.java, however these methods return the same types as in [1], but without generic inputs. Codegen can be updated to use these where possible 3) We can replace the types returned by the primitive-specialized methods with more efficient collection implementations without impacting behavior because we already have validation against nulls.

this sequencing is helpful because it enforces consistent non-nullness for all conjure collections, rather than based on specific types being used.

[Shibi-bala]

new generic list factory methods ConjureCollections which do not allow null values + update codegen to use them

@carterkozak Just to clarify this, should these new non-null ConjureCollections methods only be used if options.nonNullCollections is true. Otherwise, this is going to cause a break right?

[carterkozak]

That's correct