Better UX / user docs

Right now our pre-map & getting ready to start doing nav workflow is fragmented, and docs live in pgo.md. There should be better UX for recording & doing loop closure, prepping all the grunt work for ready to nav.

Having good docs is a first.

Then, may consider having cli flow, think about we have 3 commands total. dimos record - they teleop the robot around. dimos map build recording.db - they get a map. dimos nav --map office.tc2.lcm - robot boots, relocalizes, accepts goals. If this flow is clean, the doc almost writes itself because there's nothing to explain.

Would be great ot have live feedback during each session

• Recording: a terminal readout showing "X frames captured, Y minutes, Z sq meters estimated" so they know it's working and when to stop.
• Map building: have a rendered top-down preview of the map when it's done so they can visually confirm progress, even consider adding a progress bar?
• Relocalization: a status line that goes from "searching..." to "localized - confidence at 94%" so they're not just staring at a blank terminal perhaps?

Synced from DIM-923 by jetson

Start by reading pgo.md and comparing its pre-map, recording, map-building, and navigation guidance with the three commands named in the issue: dimos record, dimos map build recording.db, and dimos nav --map office.tc2.lcm. Done should mean a coherent, usable workflow guide; the proposed live feedback and CLI changes are broader follow-up considerations.