fix(highlight): resolve highlights in the frame of the locator

[Ashraf Ali (ashrafiucse)]

Summary

• HighlightController was resolving every entry from the main frame, so frame.locator(...).highlight() highlighted elements in the wrong frame (1.63 regression from chore(highlight): resolve highlights periodically in HighlightController #42277)
• Thread the originating frame through the highlight entry and resolve relative to it; key entries by frame as well, so the same selector can be highlighted from different frames
• Regression tests: frame-relative highlight, same selector across frames, highlight surviving frame navigation

Fixes #42850

[Ashraf Ali (ashrafiucse)]

Closing since #42868 landed the same fix. Two scenarios I had covered here that aren't on main: highlighting the same selector from different frames, and highlights surviving frame navigation — happy to send them as a follow-up if useful.