cfu service: deduping common response helper methods

[sanjay-nagesh]

Fixed Issue #388

[Copilot]

Pull request overview

This PR addresses Issue #388 by deduplicating CFU “common response” construction logic (invalid FW version + content rejection) into a shared helper module and updating existing CFU components to use it.

Changes:

• Added cfu-service-internal response helper functions in a new responses module.
• Updated Buffer and Splitter to call the shared helpers instead of maintaining duplicate local methods.
• Wired the new module into the crate via lib.rs.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
cfu-service/src/splitter.rs	Replaces local helper methods with calls into crate::responses for common response creation.
cfu-service/src/buffer.rs	Replaces duplicated response-building helpers with shared crate::responses utilities.
cfu-service/src/responses.rs	Introduces shared helpers for invalid FW version responses and content rejection responses.
cfu-service/src/lib.rs	Adds the internal responses module to the crate.

[RobertZ2011]

@sanjay-nagesh You'll need to rebase this branch to pull in the latest changes from main before it can be merged.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

[Copilot]

The local variable name dev_inf is unclear/abbreviated; consider renaming to something more descriptive (e.g., dev_info or component_info_entry) to make the helper’s intent easier to read/maintain.

Suggested change

	let dev_inf = FwVerComponentInfo::new(FwVersion::new(INVALID_FW_VERSION), component_id);
	let comp_info: [FwVerComponentInfo; MAX_CMPT_COUNT] = [dev_inf; MAX_CMPT_COUNT];
	let component_info_entry = FwVerComponentInfo::new(FwVersion::new(INVALID_FW_VERSION), component_id);
	let comp_info: [FwVerComponentInfo; MAX_CMPT_COUNT] =
	[component_info_entry; MAX_CMPT_COUNT];

[Copilot]

The standalone // line is unnecessary, and these look like function docs; consider converting them to rustdoc comments (/// ...) so they stay attached to the functions and match the style used elsewhere in this crate.