Tapping an intra-message #fragment link in a rich-data bubble now scrolls
the chat so the matching anchor lands just below the content-area top,
expanding any enclosing collapsed <details> first. Anchors come from
server/AI-sent InstantPages (block .anchor or inline RichText.anchor); the
compose path is unchanged.
- InstantPageV2View.anchorFrame(name:) resolves an anchor's frame in the
live layout (text/codeBlock/thinking/details/table), mirroring findTextItem.
- instantPageAnchorPath(in:name:) is a pure model walk returning the
<details>-sibling-ordinal path to an anchor; its recursion set matches
exactly the containers the V2 layout flattens through layoutBlock
(.blockQuote/.cover/.list .blocks), keeping ordinals consistent with the
layout's detailsIndexCounter.
- InstantPageV2View.firstCollapsedDetails(forOrdinalPath:) maps that path to
the first not-yet-expanded details' live index (read, never reproduced).
- The rich bubble fills the two stubbed seams: getAnchorRect, and a
fragment-link route in tapActionAtPoint that drives a resolve -> expand ->
scroll state machine (pendingScrollAnchor + progress guard + a
post-relayout hook). Taps are gated off while the message streams.
Verified by the full Bazel build; runtime behavior not yet exercised.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
