[internal]: screenshot instead of snapshot polishing

[Skn0tt]

Before we ship "screenshot instead of snapshot", let's smooth out the rough edges.

• [ ] attempt to select text causes image drag-n-drop - https://github.com/microsoft/playwright/pull/33089
• [ ] click target is misplaced
• [ ] discoverability: add a hint inside canvas in DOM snapshot - https://github.com/microsoft/playwright/pull/33092
• [ ] #33115

[mxschmitt]

FYI, reverted patches:

• https://github.com/microsoft/playwright/pull/32905
• https://github.com/microsoft/playwright/pull/32832

[Skn0tt]

I've opened three PRs for this, and broke the fourth item out into its own exploration subissue.