fix(desktop): rebuild thread autoscroll on use-stick-to-bottom

apps/desktop/src/store/thread-scroll.ts

@@ -1,8 +1,13 @@
 import { atom, type WritableAtom } from 'nanostores'
 
-// `$threadScrolledUp` flips the instant the viewport leaves the bottom (dims the
-// composer / status stack). `$threadJumpButtonVisible` trips a little further up
-// (~10px) so the floating jump control only shows once meaningfully away.
+// "Is the thread parked at the bottom" is owned by use-stick-to-bottom inside
+// ThreadMessageList (the scroll container). That state lives only in that
+// subtree, so ThreadMessageList mirrors it into these atoms for the composer,
+// status stack, and floating jump button — all of which render OUTSIDE the thread.
+//
+// `$threadScrolledUp` dims the composer / status stack; `$threadJumpButtonVisible`
+// shows the floating jump control. Both track `!isAtBottom` today, but stay
+// separate so their thresholds can diverge again without touching consumers.
 export const $threadScrolledUp = atom(false)
 export const $threadJumpButtonVisible = atom(false)
 
@@ -13,17 +18,19 @@ const setter = (target: WritableAtom<boolean>) => (value: boolean) => {
   }
 }
 
-export const setThreadScrolledUp = setter($threadScrolledUp)
-export const setThreadJumpButtonVisible = setter($threadJumpButtonVisible)
+const setScrolledUp = setter($threadScrolledUp)
+const setJumpButtonVisible = setter($threadJumpButtonVisible)
 
-export const resetThreadScroll = () => {
-  setThreadScrolledUp(false)
-  setThreadJumpButtonVisible(false)
+export const setThreadAtBottom = (isAtBottom: boolean) => {
+  setScrolledUp(!isAtBottom)
+  setJumpButtonVisible(!isAtBottom)
 }
 
-// Cross-component bridge: the jump button lives by the composer, the re-arm +
-// pin machinery lives in the virtualizer. The virtualizer registers a handler;
-// the button fires it. Mirrors the composer focus/insert emitter pattern.
+export const resetThreadScroll = () => setThreadAtBottom(true)
+
+// Cross-component bridge: the jump button lives by the composer, the viewport's
+// `scrollToBottom` lives inside the thread. The bridge registers a handler; the
+// button fires it. Mirrors the composer focus/insert emitter pattern.
 const handlers = new Set<() => void>()
 
 export const onScrollToBottomRequest = (handler: () => void) => {
@@ -33,3 +40,25 @@ export const onScrollToBottomRequest = (handler: () => void) => {
 }
 
 export const requestScrollToBottom = () => handlers.forEach(handler => handler())
+
+// Inline edit grows a sticky human bubble. Fire on pointerdown so the viewport
+// escapes stick-to-bottom before focus/layout; close clears the edit flag when
+// the inline composer unmounts.
+const editOpenHandlers = new Set<() => void>()
+const editCloseHandlers = new Set<() => void>()
+
+export const onThreadEditOpen = (handler: () => void) => {
+  editOpenHandlers.add(handler)
+
+  return () => void editOpenHandlers.delete(handler)
+}
+
+export const notifyThreadEditOpen = () => editOpenHandlers.forEach(handler => handler())
+
+export const onThreadEditClose = (handler: () => void) => {
+  editCloseHandlers.add(handler)
+
+  return () => void editCloseHandlers.delete(handler)
+}
+
+export const notifyThreadEditClose = () => editCloseHandlers.forEach(handler => handler())