module: cadence: rework module to use sink/source api

[softwarecki]

Rework the cadence ipc3 module variant to only use the sink/source api to prepare sof for the full transition to pipeline 2.0.

Make cadence_copy_data_from_buffer() shared across both ipc3 and ipc4 variants. Add a common cadence_copy_data_to_buffer() function. Remove the unnecessary const modifier from sink_buffer_start and eliminate redundant type casts.

[Copilot]

Pull request overview

This PR reworks the Cadence codec module (IPC3 variant) to use the sink/source APIs (aligning with the pipeline 2.0 transition), and consolidates ring-buffer wrap copy logic into shared helpers used by both IPC3 and IPC4 variants.

Changes:

• Added shared ring-buffer copy helpers cadence_copy_data_from_buffer() and cadence_copy_data_to_buffer() to remove duplicated wrap-handling logic.
• Converted IPC3 Cadence processing to the sink/source .process interface (instead of the deprecated .process_raw_data interface).
• Simplified IPC4 output copy path to use the new shared helper and adjusted sink_buffer_start mutability.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
src/include/sof/audio/module_adapter/module/cadence.h	Declares new shared ring-buffer copy helper APIs.
src/audio/module_adapter/module/cadence.c	Implements the shared ring-buffer copy helper functions.
src/audio/module_adapter/module/cadence_ipc4.c	Removes local copy helper and uses the shared helper for sink writes.
src/audio/module_adapter/module/cadence_ipc3.c	Switches to sink/source .process API and updates data movement to use shared helpers.