fix(collaborative-prosemirror): never throw restoring the selection on a remote update

[mmamedel]

Problem

ProseMirrorFacade.set() maps the previous selection through the applied transaction and reinstates it with TextSelection.create():

const newAnchor = tr.mapping.map(selection.anchor);
const newHead = tr.mapping.map(selection.head);
tr.setSelection(TextSelection.create(tr.doc, newAnchor, newHead));

When a remote update changes the document such that the mapped position no longer points into inline content — e.g. it removes the trailing blocks that held the local caret — TextSelection.create() throws:

TextSelection endpoint not pointing into a node with inline content (doc)

The consequence is worse than a caret glitch: set() also runs inside PeritextBinding.bind()'s initial syncFromModel(), so the exception aborts the entire binding. The editor stays permanently unwired, and every subsequent local edit is applied to ProseMirror only and silently lost — nothing throws afterwards, which makes it very hard to diagnose.

We hit this in production in a collaborative screenplay editor built on these packages: a client resuming a session (server snapshot replacing the body while the caret sat in later content) lost all subsequent typing on reload.

Fix

Use TextSelection.between(), ProseMirror's non-throwing constructor, which clamps to the nearest valid text selection. The same hazard exists in setSelection() (a CRDT-space selection can resolve around block boundaries mid-sync) — guarded identically.

Tests

New spec ProseMirrorFacade.selection-restore.spec.ts:

• reproduces the exact failure (caret in a trailing paragraph + a remote set() that removes it) — fails with the quoted error before this change, passes after;
• pins that in-range mapped selections are still restored exactly (no behavior change for the normal case).

All 13 existing collaborative-prosemirror suites pass unchanged (719 tests).