European Open Procedure, Pursuant To Art. 71 Of The Legislative Decree. N. 36/2023, Finalized, Pursuant To Art. 59, Paragraph 3, Of The Legislative Decree. N. 36/2023, To The Conclusion Of A Framework Agreement Without Subsequent Competitive Comparison, For The Awarding Of Corrective Maintenance Work In Failure And Extraordinary Maintenance Of Building Structures And Water, Heating/Air Conditioning And Electrical Systems