The README's "What is real, and what is not yet" names, in a realtor's words, what the app does today #216

Split from #191. The section was written early and omits most of what the app now does; a realtor reads it as the product's honest limits.

Done looks like:

• [x] The Real bullets name, in plain words (no API terms), each of: downloading your deals and bringing them back, times and places for closings, inspections and walkthroughs, appointments too close together on the same day flagged, a listing agreement that expires before closing flagged, home-anniversary notes drafted for your approval, the Activity record and its spreadsheet, commission and your year. Each claim is checked against src/routes.ts; nothing the code does not do is claimed.
• [x] Each one links to the README section that shows how; the test from the blocking issue passes on them.
• [x] The Simulated and phase two bullets still say no email or text message leaves the app.
• [x] Only README.md changes. bun test passes.

Risks: none to the running app. A red preview with only README.md changed is #195's, not this issue's: say so in the pull. Brief: a writer or a builder (mason).

Reviewed pull #230 at its head: ticked The Real bullets name, in plain words (no API terms), each of: downloading your deals and bringing them back, times and places for closings, inspections and walkthroughs, appointments too close together on the same day flagged, a listing agreement that expires before closing flagged, home-anniversary notes drafted for your approval, the Activity record and its spreadsheet, commission and your year. Each claim is checked against src/routes.ts; nothing the code does not do is claimed.; Each one links to the README section that shows how; the test from the blocking issue passes on them.; The Simulated and phase two bullets still say no email or text message leaves the app.; Only README.md changes. bun test passes..