[18ZOO] Display stock market metadata

[carlorusso1984]

Closes #12723

Change from:

To:

Summary

• attach appreciation thresholds, dividends, and president bonuses to 18ZOO share-price metadata
• render metadata in enlarged 2D stock-market cells while preserving ledge arrows
• safely handle sparse 2D markets and retain their existing layout
• add regression coverage for 18ZOO market prices, types, and metadata

Shared renderer audit

• audited the shared grid_2d renderer across 60 two-dimensional stock-market definitions; one-dimensional, zigzag, and hexagonal markets use separate renderers
• confirmed that 18ZOO is the only game assigning SharePrice#info, so only 18ZOO selects the enlarged metadata layout
• confirmed through DOM measurements that standard markets retain 50x50 cells while 18ZOO uses 70x70 cells
• identified 20 sparse 2D market definitions and verified that flatten.compact safely ignores empty cells, addressing the failure mode of the reverted 2023 implementation
• manually checked representative layouts in the browser:
  • 1880: sparse stepped market
  • 1822: large 15-row market with 39 empty cells
  • 1866: very wide 4x37 market
  • 18MS: compact market without empty cells
• all sampled markets preserved their existing dimensions, ledge arrows, colors, scrolling, and legends

Testing

• docker compose exec rack bundle exec rspec spec/lib/engine/game/g_18_zoo/game_spec.rb (179 examples, 0 failures)
• docker compose exec rack bundle exec rubocop lib/engine/game/g_18_zoo/game.rb assets/app/view/game/stock_market.rb spec/lib/engine/game/g_18_zoo/game_spec.rb
• git diff --check
• manually verified the Market tab in local 18ZOO Map C
• manually verified 1880, 1822, 1866, and 18MS through the shared 2D renderer

[perwestling]

Reviewed with AI assistance by Mistral Vibe

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✅ Strengths

• Implements requested feature (closes #12723)
• Comprehensive change: adds appreciation thresholds, dividends, president bonuses
• Clean UI implementation with enlarged 2D cells for metadata
• Extensive verification:
  • Audited shared grid_2d renderer across 60 markets
  • Confirmed 18ZOO is only game using SharePrice#info
  • Manual testing of 1880, 1822, 1866, 18MS (appropriate for frontend code)
• All backend tests pass (179 examples, 0 failures)
• RuboCop passes
• Adds backend regression tests for metadata

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❓ Questions

• Have you considered adding a screenshot of the new UI to the PR description?

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✅ Verdict: Approve

Well-crafted implementation. The frontend changes are appropriately verified through manual testing, and backend changes are well-tested.

Remove AI assisted approval.