fix(fusion_plating_jobs): vertically center the full-width QR (no-tags external)

The no-tags QR used line-height centering, which wkhtmltopdf renders slightly
high (extra white at the bottom). Switched to a single-cell table with
vertical-align:middle (same mechanism as the with-tags case) so the QR centers
in its cell with balanced top/bottom margin. Verified live (WO-30072).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

fusion_plating/fusion_plating_jobs/report/report_fp_job_sticker.xml

@@ -198,7 +198,7 @@
                         </tr></table>
                     </t>
                     <t t-else="">
-                        <div class="qffull"><span class="qfwrap-full"><img t-att-src="_qr"/></span></div>
+                        <table class="qftbl"><tr><td><span class="qfwrap-full"><img t-att-src="_qr"/></span></td></tr></table>
                     </t>
                 </div>
                 <div class="r-fld rule">