Change Report advanced

[tpurschke]

• [x] refine rule change report (show diffs precisely)
• [ ] add object change to changes report (make this an optional setting in report filter)
• [ ] add implicit change reporting (object change causing rule change)
• [ ] turn BlazorTables Rules/Changes into separate components/files?
• [ ] #2506
• [x] remove wrong "diff" sometimes occuring in service field (maybe related to missing order_by statement?):

4/19/2021 7:26:45 AM | rule modified | outbound 2 10.0.0.49 | dmz | 240.69.135.119 (240.69.135.119/32)+ 244.97.176.185 (244.97.176.185/32) | wan1 | valve_10.0.0.49 (10.0.0.49/32) | valve_ports PINGdiff: PING valve_ports
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