printedparts stage 5: the ledger - restock/adjust with badge attribution

Badge resolver copied from the USB contract (SSO digits, 0<digits>BZ
PayNo wrap) with names from the employees directory and the
unknown-badge policy setting; deliberately copied rather than
cross-imported so the contract test stays green. Restock and adjust
write the ledger row and move the cached quantity in one commit -
the single-commit invariant every write path must use. Adjust
requires a reason and refuses to drive stock below zero. Detail page
gains Restock/Adjust modals. Seven tests cover minting, the
cache==ledger invariant, badge shapes, policy toggle, and auth.

plugins/printedparts/services/__init__.py

@@ -0,0 +1 @@
+"""Printedparts plugin services."""