Add a first-class `checked: Bool?` to InstantPageListItem (orthogonal to the
ordered-list `num`), replacing the prior sentinel-string-in-num prototype.
- Data model: enum third associated value on .text/.blocks; Postbox + a new
FlatBuffers `checkState` tri-state field (0=nil,1=unchecked,2=checked,
backward-compatible); Equatable.
- Transmission: read/write the native API `checkbox`=flags.0 / `checked`=flags.1
bits on all four PageListItem / PageListOrderedItem constructors, so checkbox
state survives the server round-trip for sender and recipients.
- Markdown: forward parser routes detected `[ ]`/`[x]` into `checked` (keeping
the real number for ordered items); reverse converter emits `- [ ]`/`- [x]`
so editing a rich message round-trips.
- Display: V1 + V2 layout detect via `item.checked`; the V2 renderer draws real
CheckNode artwork (was a placeholder); preview text shows a checkbox glyph
instead of leaking the old sentinel.
Spec: docs/superpowers/specs/2026-05-27-instantpage-list-checkbox-design.md
Plan: docs/superpowers/plans/2026-05-27-instantpage-list-checkbox.md
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds a base getAnchorRect on ChatMessageBubbleContentNode, the rich-bubble
override (including titleHeight in details recursion), bubble-item
forwarding to content nodes, ChatControllerInteraction.scrollToMessageIdWithAnchor,
and a scrollToAnchor that lands the anchor at the top of the content area /
its line. Threads anchor/scroll params through ChatController and related
call sites.
Adds three thin forwarding methods on TelegramEngine.Resources
(fetch, status, data) over MediaBox, then migrates SaveToCameraRoll's
three public functions to use them, drops import Postbox from the
module (source + Bazel dep), and updates all 23 call sites across 14
caller files atomically.
Bundled: spec + fix + plan + C1 facades + C2 SaveToCameraRoll rewrite
+ BUILD dep drop + CLAUDE.md outcome.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
