--weekly (-w): show the summary for the entire week containing the
given day, fetching from Joplin or parsing all tables in the file
--short (-s, repeatable):
-s alone: one line per project label + total
-s --weekly: per-day project totals with day subtotals
-ss --weekly: one line per day with right-aligned date + week total
Add filter_week_sections() to parser.py to split a document into
(date, rows) pairs for a given ISO week. Add print_summary_short(),
print_summary_weekly(), print_summary_weekly_short(), and
print_summary_weekly_totals() to output.py.
