Strengthen the Assumption's octave against a demoted St. John Eudes

Demote St. John Eudes (Aug 19) from Duplex to Semiduplex -- too minor
a confessor to keep outranking the Assumption's octave. To make that
demotion actually cede the day, raise the Assumption's octave to
`wins: duplex` (same pattern already used by Pentecost's octave), so an
ordinary-day tie no longer automatically favors the occurring saint.

Promote St. Thomas of Canterbury (Dec 29) to Duplex so he keeps
winning against the Christmas octave stack now that ordinary-day ties
are no longer a given.

Also add a closing-day tie-break to octave-vs-octave precedence
(pickWinningOctave): when two active octaves tie in rank, the one on
its own closing day now wins the label contest, ahead of the existing
"more recently started" tie-break. Needed because Assumption's day 3
and St. Lawrence's own closing day (Aug 17) now tie at Duplex, and the
closing day should still govern that date's label.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/data/calendar/saints/assumption.yml

@@ -10,5 +10,16 @@ rank: duplex-1-classis
 common: common-of-the-bvm
 propers: "assumption"
 # Has a real octave (Aug 15-22) -- see calendar/types.ts's OctaveConfig.
+# Strengthened to `wins: duplex` (2026-08 user decision), same pattern
+# as pentecost-sunday.yml's own override -- a Semiduplex saint no
+# longer just ties (and, by the ordinary-day tie rule, wins) an
+# ordinary octave day here; it loses outright to the octave instead.
+# Concrete motivation: st-john-eudes.yml's demotion to Semiduplex only
+# actually cedes Aug 19 to the octave because of this. Side effect
+# accepted by the user: st-damasus.yml (Dec 11, Immaculate Conception's
+# octave) and st-nicholas-of-tolentino.yml (Sep 10, Nativity of the
+# BVM's octave) are unrelated octaves not touched by this change, so
+# they're unaffected -- this only strengthens Assumption's own octave.
 octave:
   enabled: true
+  wins: duplex