nx_pub_receipt_loop.nx

nx_pub_receipt_loop.nx -- the RETURN-AND-REPORT loop, run end-to-end on the SOVEREIGN store (operator: "push to the publisher and get the receipt it's published" + "no tsv -- nishi ecosystem only"). Receipts live in a content- addressed nx_seg_store (knowledge/store/receipts), NOT a flat file. It (1) publishes a REAL artifact through the publisher's atomic pub_deploy to a SAFE LOCAL liveroot (no NAS, #26), re-verifies the served bytes, emits a SIGNED receipt to the seg_store, then queries it back + verifies the signature with the PUBLISHED pubkey; and (2) emits HONEST HELD receipts for the 2 outward HR stores still queued (publisher R6 holds outward for operator approval).