enlarge journal calendar cells and pair day/title on one line

- calendar-cell-journal: bump min-height 44px -> 76px, scale up date/dot/title font sizes
- journal calendar titles were centered; left-align them
- rework JournalCalendarDay: replace separate category_colors/titles lists
  (mismatched lengths, no way to pair a dot with its title) with a single
  entries list of (color, title) pairs so the dot and its title render on
  the same non-wrapping row per entry

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

tests/test_journal_service.py

@@ -285,7 +285,7 @@ def test_get_monthly_journal_summary_counts_entries_per_day(db_session, test_use
 
     summary = journal_service.get_monthly_journal_summary(db_session, test_user.id, today.year, today.month)
     assert summary[today].total_count == 2
-    assert summary[today].category_colors == ["#ff0000"]
+    assert [e.color for e in summary[today].entries] == ["#ff0000", "#ff0000"]
 
 
 def test_get_day_entries_returns_entries_for_that_date(db_session, test_user):