Add Linear XLSX follow-up import

docs/circuit-list-editor-known-limitations.md

@@ -9,14 +9,11 @@
 - Named and automatic logical project snapshots can be listed and restored
   through the project page with persistent Undo/Redo. Automatic snapshots are
   created every 25 revisions and only their newest 12 entries are retained.
-- The current Revit/CSV foundation and confirmed initial import are a legacy
-  starting point. The active Phase-14 plan replaces them with the Linear XLSX
-  exchange and exact Worksharing-ID identity.
-  R2 must pass a real Linear return-import check before database cutover in R3.
-  Existing-row assignment, move and detach plus creation of an external-only
-  row in an existing or newly created circuit have atomic persistent commands.
-  Their API planning and editor UI, follow-up import, conflict review and return
-  export are pending.
+- Die Linear-XLSX-Anbindung bis R9 ist umgesetzt: Erst- und Folgeimport,
+  Objektplanung und Editorzuordnung, strukturtreue Rückgabe sowie bestätigtes
+  Löschen fehlender Objekte verwenden persistente Commands. Offen ist die
+  R10-Härtung des gesamten Ablaufs mit mehreren Tausend synthetischen Objekten,
+  Messungen sowie Snapshot-/Transfer- und Neustarttests.
 - Persistence currently targets local SQLite; PostgreSQL is an architectural option, not an implemented runtime.
 - The global device library supports basic CRUD and copy operations, but has no
   versioning, permissions or controlled synchronization model.