layerling 1.80.0

• The guide says how far a pattern spiral goes (#412): The pattern's radius change was described as making a flat spiral, but an angle above 360° counts as a full circle and there are at most 100 copies, so it winds once around at most. The guide now says so in every language. Pointed out by @geoff315 on GitHub.
• Danish: The whole interface and the 16 chapters of the guide are in Danish (Dansk), with the language list and the guide's language switch. It is picked automatically for a browser set to Danish. It is not marked complete, so sentences added later show in English until their Danish follows. Made by @Henrikth12 with AI help and read through by a Danish speaker; wrong words are fixed with a small pull request (#411).
• Undo steps survive a reload when the last step was made on a face workplane (#390): A design whose last step was made with the workplane on a face lost its whole undo history when it was loaded again, for instance after an update with Save and reload: the design came back complete, but Undo, Redo and the history view were greyed out. Loading compared the stored last step to the base plate instead of to the workplane it was made on, found a difference and threw the history away. It compares to the step's own workplane now. Reported by @gquiring on GitHub.
• Framing square: the height arrow stands where the guide lines meet: The green arrow for the height stood at a corner of the body of its own, apart from the two guide lines along the floor. It now stands at the point where they meet. Suggested by DrJones in the forum.
• The README says what a network copy can and cannot do offline (#409): Installing layerling as an app and using it offline need an https:// address (or localhost), and the offline files (sw.js) are only in the static export, not in the Docker image or npm run start. Both are now written under Docker and Static Hosting, and so is LAYERLING_ALLOWED_DEV_ORIGINS, which lets the development server be opened by a name such as myhost.local. Reported on GitHub.
• French names of four shapes corrected (#406): The shapes were called "Printemps" (the season) for Spring, "Équipement" for Gear, "Grenier" (an attic) for Loft and "Tube plié" for Bent Tube. They are now "Ressort", "Engrenage", "Lissage" and "Tube courbé", as is "Engrenage à chevrons" for the herringbone gear, and the French guide uses the same words. Suggested by @jeromefc50.
• A backup restored twice no longer doubles your designs (#407): Restoring a backup ZIP added every design as a new one, so restoring it into the same browser again left duplicates behind. A design that is already there (same name and same creation time) is now skipped, and the notice says how many were. The tooltip of "Back up all" also names the button that restores a backup, "Open a design or import geometry". Reported by @danyvanimpe-lab on GitHub.
• Push a flat face out or cut a pocket in (#404): A thicker wall, a raised pad or a pocket on a finished part took a workplane on the face, a traced sketch, an extrusion and a group, and on an imported STL there was no other way. A new tool, Face, in the Modify group next to the hole pattern, does it in one step: click a flat face, go out or in, and set the depth, an inset from the face's edge and a corner radius that rounds the inner corners too. A pocket goes no deeper than the body behind the face. What it adds is an ordinary sketch body grouped with the body, so Edit group, Edit sketch and Undo work as usual. On the top or the bottom of a plain sketch body it keeps that body's own outline, set in exactly by the CAD kernel where it can, and the new part keeps its inset when it is resized; on any other face, and on every face of an imported mesh, it follows the face's triangles. Also as the MCP action layerling_push_face. Contributed by @mlugo-apx.