Show dialog when active contributors per month limit is hit

[ValentinBuira]

This PR add a new dialog when user try to sync while they have already hit the active contributor per month limit

Note for reviewer the error live and is triggered in synchronizationerror and synchronizationmanager

Resolve https://github.com/orgs/MerginMaps/projects/15/views/1?pane=issue&itemId=86203521

[github-actions]

Pull Request Test Coverage Report for Build 11856013602

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 59 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.03%) to 60.432%

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Files with Coverage Reduction	New Missed Lines	%
input/core/merginapi.cpp	3	78.95%
input/app/synchronizationerror.cpp	6	33.33%
input/app/mmstyle.h	50	1.94%

Totals
Change from base Build 11788282153:	0.03%
Covered Lines:	7881
Relevant Lines:	13041

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💛 - Coveralls

[VitorVieiraZ]

Looks good to me. I’ve left only comments about code styling and a suggestion for when apiSupportsSubscriptions is false.