Enhance concurrency handling and improve documentation

[FrozenLemonTee]

No description provided.

[Copilot]

Pull request overview

This PR updates the primitives concurrency model so operations and special members use policy-controlled load/store semantics, and expands test coverage for concurrent behavior and object semantics.

Changes:

• Add concurrency::none access handler (load/store/compare_exchange) and update policy tests accordingly.
• Make primitive copy/move special members use load()/store() and centralize access-handler gating.
• Route operation dispatch through lhs.load()/rhs.load() and add new high-concurrency + copy/move tests; update .gitignore.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tests/basic/test_policies.cpp	Adjusts expectations for access-handler availability under concurrency::none.
tests/basic/test_operations.cpp	Adds a high-concurrency stability test for binary ops and verifies copy/move special members.
src/primitive/impl.cppm	Implements copy/move special members using load()/store() and factors access gating into a helper.
src/policy/impl.cppm	Adds concurrency::none access handler implementation for primitive load/store/CAS.
src/operations/dispatcher.cppm	Switches dispatcher operand reads from .value() to .load().
.gitignore	Ignores out/ and normalizes the /.cache entry formatting.