### Describe Your Changes
- Show the time range in the tooltip when hovering over staircase
graphs.
- Use bolder lines for staircase graphs.
- Increase the number of steps on the staircase graph to 100.
- Reduce the maximum width of the tooltip to 1/3 of the screen.
- Insert only the label name under the cursor into the query input field
when `Ctrl`-clicking the line legend.
See [this
comment](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6545#issuecomment-2336805237).
### Checklist
The following checks are **mandatory**:
- [ ] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
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Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>