Bump virtual-core to 3.19.11 and remove the getOffsetForIndex stopgap #7

Follow-up to #6.

When

Once @tanstack/virtual-core@3.19.11 is on npm. It contains the fix for getOffsetForIndex answering from stale measurements (TanStack/virtual#1363, issue TanStack/virtual#1361). The release is pending in TanStack/virtual#1364.

Bump

• Replace wwwroot/tanstack-virtual-core.js with the jsDelivr +esm bundle of 3.19.11, and update the README's provenance table (version, SHA-256) and the "Coverage vs." heading.
• Re-verify the private surface the interop uses: _willUpdate, _didMount, itemSizeCache, itemSizeCacheVersion, pendingMin.
• Read the 3.19.9, 3.19.10 and 3.19.11 changelogs for anything else the interop depends on.

Remove the getOffsetForIndex stopgap

• The refreshMeasurements() call in getOffsetForIndex in adaptive-virtualize-interop.js.
• The one in scrollToIndex: 3.19.11 also aims the first scrollToIndex write from the current measurements.
• Its row in the README's stopgap table.

Keep the other refreshMeasurements() calls (takeSnapshot, getSnapshot, before resizeItem). They cover this wrapper's own direct writes to itemSizeCache, which the upstream fix does not.

GetOffsetForIndex_RightAfterARowAboveChanges_UsesTheSizesTheVirtualizerUses has to stay green with the refresh removed.

Also on this bump

• Fling stopgap goes too. 3.19.9 already contains fix(virtual-core): stop a touch fling for a command issued during it on Android too TanStack/virtual#1347, so the overflow toggle in runScrollCommand and its README row can be removed. ScrollToIndex_WhileATouchFlingIsMovingTheList_StopsTheMomentumBeforeWriting has to stay green; check a scroll command during a fling on an Android phone as well.
• ⚠️ The RTL stopgap stays. fix(virtual-core): restore programmatic scrolling in RTL elements TanStack/virtual#1291 is still open and is not in 3.19.11. Removing the scrollToFn negation now breaks scroll commands in IsRtl lists; keeping it after a release that contains that fix negates the write twice. IsRtl_ScrollToIndex_BringsTheItemOnScreen fails in both cases.