feat(cardshed): MVP shipping gate (M17)

[w7-mgfcode]

Sub-issue of #146. PRP 3 milestone M17 (MVP shipping gate). Reference: PRPs/cardshed-03-experience-prp.md lines 1056–1073.

This is the verification slice — no new features. Confirms the umbrella's done-when criteria across the assembled stack.

Scope

• apps/ui/e2e/full-round.spec.ts — Playwright full-round e2e
• Final verification pass across all 16 prior milestones

Acceptance

• npm run test — vitest unit suite green (apps/ui AND apps/core)
• npm run typecheck — tsc --noEmit green (apps/ui AND apps/core)
• npm run lint — eslint --max-warnings 0 green (apps/ui AND apps/core)
• npx playwright test — full-round e2e green
• Skill: agent-browser captures dogfood-output/<utc>/m17-mvp-gate/ with the full chain:
  • MainMenu → PlayerSetup → 4 player names → Table → AttackSelect → DefenseSelect → RoundResult
• docs/SCREENS/ has one .md per screen with Stitch provenance recorded
• No console.error in any screen
• All sub-issues feat(cardshed): table render + privacy splash (M5+M6) #147, feat(cardshed): scaffold apps/ui + design system (M1+M2) #148, feat(cardshed): pre-match screens — MainMenu + PlayerSetup (M3+M4) #149, feat(cardshed): round/match results + settings + rules help (M10+M11) #150, feat(cardshed): analytics + Level-0 bot (M15+M16) #151, feat(cardshed): attack + defense + phase transitions (M7+M8+M9) #152, feat(cardshed): a11y + responsive + juice (M12+M13+M14) #154 closed

Common bugs (from PRP 3)

• Skipping the dogfood-output capture (per .claude/rules/ui-design-pipeline.md §3 = blocker)

Complexity

M = ~3 hours (mostly verification).