Making cauldorns useable to visiting pubic at your village is kinda tough right now, since enabling "theft" permission allows not only to take completed products, but also to lift the entire cauldron. I suggest two options to fix this.
Option 1: Differentiated permissions.
Allow taking items out of "workshop" containers on Rummage instead of theft permission (at least if the ownership token, like the one for dropped items, is yours). Only allow lifting on Theft.
This might also be useful for Tar Kilns, Sawmills, etc. but they can't be lifted so this is waaay less of a concern
Option 2: Chains.
Allow crafting an item called chains (I suggest 10-12 metal nuggets). Besides being a metal rope, you can use it to chain down items. Items with chains cannot be lifted until the chains are removed or destoyed (either requiring Vandalism). Chains are displayed visually on the bottom of an item. Chains can be locked with a lock (or even crafted requiring one), and only removed with a key. Slave key allows removing the chains, you only need Master Key to change the lock or re-key it. Also stops anyone from moving your favorite cart/barrel/metal cabinet/safebox away.