docs(badges): update print behavior docs + Zebra test day plan

- MODULE__AE_Events_Badge_Templates: rewrite Print Layout Architecture
  section with accurate cross-browser behavior table and Chrome margin
  guidance
- PROJECT__AE_Events_Badges_Review_Print: add TASK 4.1 print CSS
  centering history; correct Chrome squish root cause explanation
- PROJECT__AE_Events_Zebra_Hardware_Test_Day: new — comprehensive
  pre-test and day-of checklists for ZC10L hardware test ~2026-03-16
- TODO__Agents: add [Badges] Zebra ZC10L Hardware Testing section

documentation/TODO__Agents.md

@@ -38,6 +38,25 @@ frontend pass the location directly in the Launcher URL without the extra lookup
 - **Badge print controls UX polish:** Scott has improvements in mind — TBD next session.
   File: `ae_comp__badge_print_controls.svelte`.
 
+### [Badges] Zebra ZC10L Hardware Testing — ~week of 2026-03-16
+Scott is renting a Zebra ZC10L for one day to do real-world badge printing tests before
+Axonius (mid-April). See `documentation/PROJECT__AE_Events_Zebra_Hardware_Test_Day.md`
+for the full checklist and prep plan.
+
+**Pre-test work (do before printer arrives):**
+- [ ] **Remove debug outlines** from `print/+page.svelte` print CSS (lime/blue/red/orange/purple/cyan)
+- [ ] **Zebra ZC10L Linux driver** — install CUPS driver package ahead of time; verify card prints
+  before burning rental time on driver setup. Check Zebra's site for Linux/CUPS driver.
+- [ ] **Wire `style_href`** via `<svelte:head>` in `print/+page.svelte` — needed so client-specific
+  CSS loads from the template's `style_href` field. Currently tracked as pending in MODULE doc.
+- [ ] **Confirm `duplex=0` hides badge back in print** — `duplex` field not yet on backend;
+  verify badge_back is suppressed for single-sided PVC. May need a manual print CSS rule until
+  the backend field lands and `properties_to_save` is updated.
+- [ ] **Set up test event + PVC template** in dev DB with `layout: badge_3.5x5.5_pvc`,
+  a few badge records with varied name lengths, HTML in fields, different badge_type_codes.
+- [ ] **Test data set:** include edge cases — very long name, HTML markup in name/affiliations,
+  badge with no affiliations, badge with all ticket/option codes set.
+
 ### [Leads] Exhibitor Lead Scanning — NEXT MAJOR FEATURE
 QR code scan at exhibitor booth → capture attendee badge data. Gated by `allow_tracking` on
 the badge. Check if `documentation/MODULE__AE_Events_Leads.md` exists for full spec.