Pipeline hygiene check

Check my pipeline records for hygiene problems since this task last
ran. Read only. Change no record.

Source: WHERE, and which view or database.
Fields that must be filled: LIST.
Stale means no activity for more than DAYS days.

Group the exceptions.

Stale. Past the staleness threshold and still open. Show the days since
last activity, highest first.
Missing fields. Records with a required field empty, naming the field.
Date in the past. Records with a close date already gone by that are
still open.
Stage and activity disagree. Late-stage records with no recent
activity, and early-stage records with a close date inside the month.
Duplicates. Records that look like the same opportunity, quoted side by
side so a human can judge.
No owner.

Per group: the count, and up to ten records with a link each. If a
group is empty, say so in one line.

Then the arithmetic. Total value of open records, total value of the
records flagged above, and the first number minus the second. Show the
subtraction. State the currency and say whether values are as recorded,
because you have no way to check them.

No forecast. No probability. No comment on any individual deal.