Pin Analysis above Roll and refresh it live while dragging

[marcinz606]

Fixes #1370

Summary

• Analysis on the Roll tab. The Analysis section moves out of the Frame page into a splitter above the outer tab stack. It shows on Roll and Frame, is hidden on Metadata / Gear / Export / Scan, and keeps the saved splitter size. Black/White Point and the other Roll cards can now be judged against the histogram without switching tabs.
• Live refresh while dragging. A drag render of the edit reads metrics back from the interactive proxy, and _update_analysis no longer skips interactive frames. The histogram, waveform, vectorscope, stats and the small slider histograms track the slider instead of waiting for release. Config-override renders (Flat peek, zone-placement preview) and the splash still skip readback, so they never replace the edit's histograms.

Cost

Headless drag (20 steps, DSC00448.ARW, offscreen, this machine's GPU):

	before	after
Chart refreshes during drag	0/20	20/20
Worker frame time (median)	1.7 ms	20 ms
_update_analysis on UI thread	—	2.3 ms/frame

Most of the added time is the metrics map_sync waiting for the GPU to finish the frame (about 11 ms). The old 1.7 ms only covered submission. Expect a longer wait on integrated GPUs. If that becomes a problem, throttle the drag readback to every Nth frame.

Test plan

• make all
• New: a drag reads metrics back and an override render does not (test_controller.py)
• New: Analysis visible only on Roll and Frame (test_right_panel_wiring.py)
• Headless app run: visibility per tab, and live histogram refresh during drag
• Manual: drag White Point on Roll on a real display, and check the drag still feels smooth on an integrated GPU

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