feat(finale): per-project presentation/Q&A durations in m:ss + config-save merge fix

- setProjectTiming stores per-project overrides in round config; phase starts
  resolve: explicit input > project override > round default
- Run Order rows get m:ss inputs per project; PhaseControls one-off overrides
  now also m:ss (shared parseClock: '7:30', '12:05', plain '7')
- CRITICAL: round.update now MERGES validated form config over the existing
  configJson — saving the Config tab was wiping projectOrder (would have
  destroyed a running ceremony) and the finals-docs upload toggle

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/unit/live-timer.test.ts

@@ -3,7 +3,7 @@
  * derives the same countdown from cursor timestamps — no client-local clocks.
  */
 import { describe, it, expect } from 'vitest'
-import { elapsedMs, remainingSeconds, formatClock } from '@/lib/live-timer'
+import { elapsedMs, remainingSeconds, formatClock, parseClock } from '@/lib/live-timer'
 
 const t0 = new Date('2026-06-11T10:00:00Z')
 const at = (s: number) => new Date(t0.getTime() + s * 1000)
@@ -72,4 +72,20 @@ describe('live-timer', () => {
     expect(formatClock(0)).toBe('0:00')
     expect(formatClock(-83)).toBe('+1:23')
   })
+
+  it('parseClock accepts m:ss, mm:ss and plain minutes', () => {
+    expect(parseClock('7:30')).toBe(450)
+    expect(parseClock('12:05')).toBe(725)
+    expect(parseClock('0:45')).toBe(45)
+    expect(parseClock('7')).toBe(420) // plain minutes
+    expect(parseClock(' 3:00 ')).toBe(180) // tolerant of whitespace
+  })
+
+  it('parseClock rejects garbage', () => {
+    expect(parseClock('')).toBeNull()
+    expect(parseClock('abc')).toBeNull()
+    expect(parseClock('5:75')).toBeNull() // seconds must be 0-59
+    expect(parseClock('-2:00')).toBeNull()
+    expect(parseClock('1:2:3')).toBeNull()
+  })
 })