The terminal's milestones screen shows each milestone's pace: issues closed per day as a sparkline and when it lands at this pace #8058

Intent: watch the big things move, from the terminal. The milestone page draws paceLine (a sparkline of pace.closedPerDay and the pace.line sentence, from readPlan's Milestone.pace in src/core/milestones.ts), but src/tui/screens/limbs.ts, the same page's door in the terminal, does not show it.

Done looks like:

• [ ] Under each milestone row on src/tui/screens/limbs.ts, one muted line: a block-character sparkline of closedPerDay (▁▂▃▄▅▆▇█, scaled to that milestone's max), then pace.line word for word. When pace.line is empty there is no line, as on the page.
• [ ] It uses the Plan the screen already reads, with no second readPlan call, and fits narrow terminals by dropping the sparkline before the sentence.
• [ ] test/tui-limbs-pace.test.ts: with a milestone whose issues closed on three different days, the screen shows the same pace.line the page shows for it, plus a sparkline of PACE_DAYS cells. A milestone with nothing closed shows no pace line.

Files: src/tui/screens/limbs.ts, test/tui-limbs-pace.test.ts. Risks: none beyond layout. Raise/Lower keys and their rows must stay where they are.

Parked by the crew: the check stayed red through 2 automatic tries (pull #8077 closed). Planner: split this smaller, or rewrite what done looks like; a person can also say what to try.