[#690] slice api

[elfenpiff]

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References

Relates to #690

[Copilot]

Pull Request Overview

This PR refactors and enhances the API for slice-based messaging in the request/response and publish/subscribe code paths. Key changes include:

• Adding the “+ ?Sized” trait bound to several generic type parameters (e.g. RequestPayload, ResponsePayload) to increase flexibility.
• Introducing new configuration structs (LocalClientConfig, LocalServerConfig) to consolidate client/server parameters.
• Adjusting dynamic versus static data segment allocation logic and updating related API calls.

Reviewed Changes

Copilot reviewed 28 out of 28 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
iceoryx2/src/service/port_factory/request_response.rs	Updated generic bounds for Request/Response payloads.
iceoryx2/src/service/port_factory/client.rs	Introduced LocalClientConfig and refactored client builder fields.
iceoryx2/src/service/header/*	Minor documentation and signature updates related to number of elements.
iceoryx2/src/port/*	Updated castings for unsized payloads and revised data segment allocation logic.
Other files	Consistent addition of “+ ?Sized” generics and adjustments to helper functions in response/request modules.

Comments suppressed due to low confidence (2)

iceoryx2/src/service/port_factory/request_response.rs:64

• Adding the '+ ?Sized' bound increases flexibility for unsized types; please verify that all downstream usages (such as transmute calls or slice operations) are compatible with unsized types to avoid subtle memory issues.

RequestPayload: Debug + ZeroCopySend + ?Sized,

iceoryx2/src/service/port_factory/client.rs:132

• The default value for 'initial_max_slice_len' is hardcoded to 1; please ensure that this value is intentional and does not lead to unexpected behavior in slice-based API usage.

initial_max_slice_len: 1,