There's no ezafe in "cherâghani", and the final "i" is part of the word. In the other two, a "y" sound is pronounced before the ezafe since the words end in a vowel ("khâne" and "cherâghhâ") and ezafe is a vowel too.

cheraghani khaneye cheraghhaye .خانه ی ما با چراغ های زرد، آبی، قرمز و سبز چراغانی شد.

Hey dude The pronounciation of "ی" is "i" for (چراغانی)cheraghani and "ی" for (خانه ی)khaneye and (چراغ های)cheragh haye Is "ye". The right gramar for your sentense is خانه ی ما با چراغ های زرد،آبی،قرمز و سبز چراغانی شد.

hi in some of them it pronounce "i" and some "ye" for example: cheraghani but khanehye