Task #749: attach executive meetings sticky header to the table

- executive-meetings.tsx: added !mt-0 to the schedule table wrapper
  (#executive-schedule-printable) to cancel the parent space-y-4 gap,
  so the dark floating header (em-sticky-thead) sits flush on the table.
- Border seam stays a single 2px line: header has border-t-2/border-x-2
  (no bottom), wrapper keeps border-2.
- No changes to sticky behavior, horizontal scroll sync, or print mode.
- tx-os tsc clean; architect review passed.

artifacts/tx-os/src/pages/executive-meetings.tsx

@@ -3265,7 +3265,7 @@ function ScheduleSection({
 
       <div
         ref={tableWrapperRef}
-        className="bg-white border-2 border-[#0B1E3F] overflow-x-auto shadow-sm print:shadow-none print:border-black print:overflow-hidden"
+        className="!mt-0 bg-white border-2 border-[#0B1E3F] overflow-x-auto shadow-sm print:shadow-none print:border-black print:overflow-hidden"
         id="executive-schedule-printable"
       >
         <table