docs: ten scenarios for connecting and splitting revenue, in click order

Written to be executed in the room. Each scenario is the sentence the accountant
will say, then the exact buttons in order, then the journal entry that appears.

Covers the one that prompted it — "the 150,000 splits 30% to this fund, 10% to
that one" — plus flat amounts, the percentage-base question, creating a missing
fund account mid-meeting, VAT inclusive vs exclusive, deferred subscription
revenue, connecting an unconnected path, breaking out an aggregate account,
undoing a change, and proving the numbers reconcile.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>