[Question] <title>triggerTime，triggered for the first time

### Question

When the same alarm occurs, the recorded time is the time when the alarm was triggered, not the time when the alarm was triggered for the first time.

Start by locating the alarm state and trigger-time recording entry point in HertzBeat, then trace how repeated occurrences update the recorded time. Done means the recorded time remains the time of the alarm's first trigger when the same alarm occurs again, with coverage for that repeated-alarm behavior.

Written by the indexing model from the issue text.