Ship one deterministic owned daily game

[dgyy]

Parent

Part of #22.

What to build

Ship one ArcadeBloom-owned browser game with a deterministic daily challenge, local streak, shareable result, and aggregate privacy-preserving measurement.

Acceptance criteria

• The same UTC date and ruleset version always produce the same challenge.
• Date rollover produces the next challenge without a deployment or editorial action.
• Scoring and result encoding are deterministic and reject impossible/tampered result shapes at trust boundaries.
• A player can complete a short session, retain a local streak, and share a result without creating an account.
• The playable experience works on keyboard and touch at supported viewport sizes.
• Measurement uses first-party aggregate events and does not require identity cookies or cross-site profiling.
• Accessibility, performance, and browser tests cover the complete daily loop.

Blocked by

None (can start immediately).