Add the Patronage of St. Joseph as a new movable feast with octave

This Duplex I classis feast (instituted by Pius IX, 1847) didn't exist
anywhere in vu's calendar. Dated per the older, pre-1955 reckoning --
Wednesday after the 2nd Sunday after Easter (Easter+17) -- rather than the
1913 Pius X reform's later placement on the 3rd Sunday after Easter
itself, per direct instruction. Mechanism: one new temporal-feast record
plus a new EASTER_OFFSET_STARTS table entry (the only code change --
everything else is the existing generic anchor-driven resolution).

Authored the feast day's own Matins reading and its full 7-day octave
(days 2/3/4/6/7/8; day 5, the Sunday, has no override in the source at
all, correctly left unauthored).

Fixed one real collateral effect: an existing fixed-year calendar test
(St. Pudentiana vs. St. Peter Celestine, 2038-05-19) broke because that
date now falls on this octave's own closing day, tying Celestine's rank
against the octave's threshold -- the app's own documented tie-break
correctly favors the octave that year. Moved the proof date to 2033.
Also bumped the PWA precache file-size cap (6 MiB -> 8 MiB) since this
content pull pushed the main bundle past the previous limit.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PhysogLP9eCeKS7JEwRi6y

src/calendar/temporal-feasts.ts

@@ -87,6 +87,7 @@ const FIXED_DATE_STARTS: [string, string][] = [['12-25', 'christmas-day']];
 
 /** Easter-offset starts (offset -> temporal feast id). */
 const EASTER_OFFSET_STARTS: [number, string][] = [
+  [17, 'patronage-of-st-joseph'],
   [39, 'ascension'],
   [49, 'pentecost-sunday'],
   [60, 'corpus-christi'],