feat(sessions): reorder and edit queued messages in place

[gantoine]

What

Two additions to the queued-messages dock (the follow-ups pinned above the composer while a turn is running):

1. Drag to reorder — each queued card is now draggable. The queue drains in array order, so the order shown is the order the messages send. Uses the existing @dnd-kit/react sortable pattern (same as sidebar folders / browser tabs), with a PointerSensor movement threshold so the card's buttons still take clicks.
2. Edit in place — the pencil now loads a queued message back into the composer for editing without removing it from the queue. Submitting the edit updates the message where it sits (same id, position, and queue timestamp) instead of appending a new one. If the message already drained or was discarded while being edited, it falls back to sending as a fresh message so nothing is lost. The card being edited is highlighted and gains a cancel (✕) affordance.

Previously the pencil ("return to editor") pulled the message out of the queue entirely; that hook (useReturnQueuedMessageToEditor) is replaced by useEditQueuedMessage / useCancelQueuedMessageEdit.

How

• core — moveQueuedMessage and updateQueuedMessage store setters; SessionService.updateQueuedMessage mirrors the enqueue normalization (cloud recomputes transport display + raw payload via getCloudPromptTransport; local stores the serialized text).
• ui — sessionViewStore tracks the active edit target per task (editingQueuedIdByTaskId); useSessionCallbacks.handleSendPrompt routes to updateQueuedMessage when an edit is in progress; QueuedMessagesDock wires the DragDropProvider + sortable cards and clears a stale edit target if the message leaves the queue.

Testing

• pnpm --filter @posthog/core typecheck + @posthog/ui typecheck — clean
• Biome lint — clean
• New packages/core/src/sessions/sessionQueueEditing.test.ts (9 tests) for the store setters; updated QueuedMessagesDock.test.tsx
• Full suites: core sessions 267 pass, UI sessions 348 pass

Not yet dogfooded in the running app — happy to do that next.

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Created with PostHog Code

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[github-actions]

React Doctor found 1 issue in 1 file · 1 warning.

1 warning

src/features/sessions/components/QueuedMessagesDock.tsx

• ⚠️ src/features/sessions/components/QueuedMessagesDock.tsx:88 Event logic handled in an effect no-event-handler

_{Reviewed by React Doctor for commit 2e5355e.}