Dashboards: Time Series panel: Tooltip timestamp changes incorrectly

### What happened? The timestamp shown in the tooltip is changing and does not correspond to the point that I am hovering nearest to. Video demonstration: https://github.com/user-attachments/assets/2b49c68b-9c93-4303-9716-0214d5a08714 ### What did you expect to happen? The timestamp shown in the tooltip should show the timestamp associated with the point that I am hovering nearest to. ### Did this work before? Yes. In my Grafana instance running v11.0.0, this works fine. ### How do we reproduce it? 1. Use the dashboard panel included below ### Is the bug inside a dashboard panel? | Key | Value | |--|--| | Panel | timeseries @ 11.0.0 | | Grafana | Grafana v11.1.4 (2355de00c6) // Enterprise | <details><summary>Panel debug snapshot dashboard</summary> ```json { "panels": [ { "datasource": { "type": "grafana", "uid": "grafana" }, "description": "", "fieldConfig": { "defaults": { "custom": { "drawStyle": "line", "lineInterpolation": "linear", "barAlignment": 0, "lineWidth": 1, "fillOpacity": 0, "gradientMode": "none", "spanNulls": false, "insertNulls": false, "showPoints": "always", "pointSize": 4, "stacking": { "mode": "none", "group": "A" }, "axisPlacement": "auto", "axisLabel": "", "axisColorMode": "text", "axisBorderShow": false, "scaleDistribution": { "type": "linear" }, "axisCenteredZero": false, "hideFrom": { "tooltip": false, "viz": false, "legend": false }, "thresholdsStyle": { "mode": "off" } }, "color": { "mode": "palette-classic" }, "mappings": [], "thresholds": { …