fix: improve slide-list overview preview sizing (#399)

[igoroctaviano]

Summary

• Fixes slide-list preview sizing when THUMBNAIL or large OVERVIEW images use the full-slide TotalPixelMatrix extent but the rendered PNG is much smaller (Heuristic for sizing overview needs improvements #399).
• Adds computeOverviewPreviewResizeFactor to derive OverviewImageViewer.resizeFactor from the 100px preview tile and matrix dimensions (replaces the removed fixed 0.3 thumbnail heuristic from fix: Thumbnail fallback and multiple thumbnail using dicom tag browser #340).
• Defers viewer mount until the preview container is laid out, then keeps the map sized via ResizeObserver.
• Adds client-side overview mini-map clamping (clampOverviewMapInViewport) for the volume viewer until the published DMV bundle includes the same sizing fix.
• Fixes mangled series UIDs from nested antd Menus and replaces nested slide Menu with a plain list.

Root cause

With resizeFactor: 1, DMV builds an extent from the full matrix while retrieveInstanceRendered returns a small overview/thumbnail PNG — the preview shows a tiny image or fails to fit the tile.

Related

• Companion to ImagingDataCommons/dicom-microscopy-viewer#266 (DMV overview sizing + integer viewport rounding). After that PR is published, bump the dicom-microscopy-viewer dependency in Slim; the client-side clamp can remain as a safety net or be simplified.

Test plan

• Unit tests for computeOverviewPreviewResizeFactor, recoverSeriesInstanceUID, and fitOverviewMapSize
• tsc --noEmit and biome check
• Slide list: https://andrey-slim-test.web.app/studies/2.25.243635437123528859218332833285423941731/series/1.3.6.1.4.1.5962.99.1.3205152386.1735416465.1639587724930.2.0
• Slide list: https://andrey-slim-test.web.app/studies/2.25.68707238542984918932186646266538960593/series/1.3.6.1.4.1.5962.99.1.1861242316.418152757.1638243814860.2.0
• Confirm OVERVIEW and THUMBNAIL fallbacks both fill the preview tile
• Volume viewer: tall/wide slides — overview mini-map usable and aligned with toolbar

Closes #399

[deepsource-io]

DeepSource Code Review

We reviewed changes in e1d5b26...2681183 on this pull request. Below is the summary for the review, and you can see the individual issues we found as inline review comments.

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PR Report Card

Overall Grade

Security   Reliability   Complexity   Hygiene

Code Review Summary

Analyzer	Status	Updated (UTC)	Details
JavaScript		Aug 6, 2026 10:37p.m.	Review ↗

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[github-actions]

Visit the preview URL for this PR (updated for commit 2681183):

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[fedorov]

@igoroctaviano this is how the second slide looks like right now... is this expected?

[igoroctaviano]

@igoroctaviano this is how the second slide looks like right now... is this expected?

Yes, if it's a wide and low case. The heuristic is using the slide dimensions to make it easier to see the overview while navigating. I can set it to be fixed height and width if that makes sense too.

[fedorov]

I admit I do not know what is a good heuristic, but when overview has the same size as the actual image, I am not sure the heuristic is good. Why is wide-and-low taking entire width, but narrow-and-tall does not take the full height?

But after all, it is not a big deal - I think this is better than what we had before, so let's merge and refine later.

[sonarqubecloud]

Quality Gate passed

Issues
10 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.2% Duplication on New Code

See analysis details on SonarQube Cloud

[igoroctaviano]

Addressed the wide vs tall asymmetry in the overview mini-map heuristic (also mirrored in ImagingDataCommons/dicom-microscopy-viewer#266):

• Prefer the same viewport fraction on both axes (45%)
• Grow only toward a hard max of 60% so wide slides no longer spill to nearly full width
• Apply the same min-side floor and max-fraction cap for tall slides

Wide and tall extremes now get matching treatment instead of width-first expansion.