ENH: Add NO_SOURCE_GROUPS option to ctkBuild macros

[kislinsk]

Disclaimer: We (MITK) are currently catching up on the latest CTK master branch
since we forked for Qt 6 back in 2023. We found a few bugs that are not caught by
your CI and mostly affect external users of CTK.

Adds an opt-out so a consumer can apply its own source_group() layout.
Without it, CTK's source_group("Resources" ...) and
source_group("Generated" ...) override the grouping the consumer set up
before calling the macro.

Note this is currently a hard break rather than a cosmetic one for consumers
that already pass the flag: CtkMacroParseArguments appends an unrecognised
token to the preceding named argument's list, so passing NO_SOURCE_GROUPS
after OUTPUT_DIR <dir> silently yields MY_OUTPUT_DIR=<dir>;NO_SOURCE_GROUPS
and the plug-in lands in a bogus directory.

Applied to all four macros (ctkMacroBuildApp, ctkMacroBuildLib,
ctkMacroBuildPlugin, ctkMacroBuildQtPlugin) for consistency.

[Copilot]

Pull request overview

Adds a NO_SOURCE_GROUPS opt-out across CTK’s build macros so external consumers can keep their own source_group() layout without CTK overriding it, and ensures the flag is properly parsed (avoiding it being accidentally appended to a preceding named argument like OUTPUT_DIR).

Changes:

• Recognize NO_SOURCE_GROUPS as a supported option in all four build macros’ argument parsing.
• Guard source_group("Resources" ...) (and source_group("Generated" ...) in the plugin macro) behind if(NOT MY_NO_SOURCE_GROUPS).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
CMake/ctkMacroBuildQtPlugin.cmake	Adds NO_SOURCE_GROUPS option parsing and skips CTK resource grouping when requested.
CMake/ctkMacroBuildPlugin.cmake	Adds NO_SOURCE_GROUPS option parsing and conditionally disables both Resources/Generated group assignments.
CMake/ctkMacroBuildLib.cmake	Adds NO_SOURCE_GROUPS option parsing and conditionally disables Resources grouping.
CMake/ctkMacroBuildApp.cmake	Adds NO_SOURCE_GROUPS option parsing and conditionally disables Resources grouping.

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[lassoan]

It looks good, I have just one general question (and a minor comment inline): Do you really want to specify NO_SOURCE_GROUPS manually for every call of all these macros? If a CTK_NO_SOURCE_GROUPS CMake option was introduced that set the desired behavior globally, then all the callers could be left unchanged.

[lassoan]

If you want to be consistent then include all arguments (including NO_SOURCE_GROUPS) here; or just do the minimum (only list NAME, as nothing else is used here).

[kislinsk]

You're right. We are using the macro(s) only in our own wrapper macro(s) so we do not need to specify the arguments over and over again, but the global solution is more elegant. I amended the commit accordingly.