Add comprehensive in-language tests for all storage types

[ironcev]

Description

This PR adds in-language tests for all all storage types, except for StorageKey and StorageVec, which are added in #7614.

Existing SDK harness tests that were testing the same functionality are deleted. This is aligned with the decision to migrate SDK harness tests to in-language tests and and at the same time strengthen the test coverage.

Checklist

• I have linked to any relevant issues.
• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation where relevant (API docs, the reference, and the Sway book).
  • If my change requires substantial documentation changes, I have requested support from the DevRel team
• I have added tests that prove my fix is effective or that my feature works.
• I have added (or requested a maintainer to add) the necessary Breaking* or New Feature labels where relevant.
• I have done my best to ensure that my PR adheres to the Fuel Labs Code Review Standards.
• I have requested a review from the relevant team or maintainers.

[cursor]

PR Summary

Medium Risk
Moderate risk because it replaces large SDK-harness coverage with new in-language tests; failures could reduce CI signal if the new tests don’t fully match prior edge cases across dynamic vs legacy storage modes.

Overview
Adds new in-language contract test programs for StorageBytes, StorageString, and StorageMap, exercising write_slice/read_slice, len, overwrites, and clear vs clear_existed behavior under both experimental_dynamic_storage modes (including slot-boundary-sized inputs).

Reworks test_types to implement Hash for several custom enums/structs (and RawPtrNewtype) so they can be used as StorageMap keys/values in the new generic test matrix, and renames the new test projects accordingly.

Removes the corresponding SDK harness projects and Rust integration tests (storage_bytes, storage_map, storage_string) from the harness workspace/modules and lockfile, shifting coverage to forc test-driven in-language tests.

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[ironcev]

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