aleting db sync: grafana db slow after upgrading from 11.4 to 12.2 due to alertingSaveStateCompressed enabled

### What happened? After upgrading grafana to v12 we started to experience sluggishness in general dashboard loading times. After investigation we discovered that grafana waits for db connections. After playing with available configurations we've found that `alertingSaveStateCompressed` FT is now enabled. A after disabling it the new version of grafana started to behave as expected <img width="852" height="299" alt="Image" src="https://github.com/user-attachments/assets/3f070646-3a4a-455e-8f29-dbc9c53cca32" /> some context: 1. we're using Mysql Aurora db for the grafana backend. 2. grafana has 2 nodes with gossip for high availability 2. we have more than 10k alerts ### What did you expect to happen? grafana to work after upgrade ### Did this work before? yes ### How do we reproduce it? none ### Is the bug inside a dashboard panel? no ### Environment (with versions)? Grafana: 11.4.5 -> 12.2.1 OS: linux Browser: Chrome DB: Mysql Aurora ### Grafana platform? A package manager (APT, YUM, BREW, etc.) ### Datasource(s)? _No response_