Add config-driven hot-path read cache for get_market with snapshot invalidation

[greatest0fallt1me]

Description

get_market is on the hot read path and re-deserializes the full struct. Add an in-instance cache keyed by market_id, invalidated whenever MarketStateManager mutates the market.

Requirements and Context

• Add MarketReadCache in markets.rs backed by env.storage().instance()
• Invalidate on every write path through MarketStateManager
• Document TTL behavior
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested Execution

1. Fork the repo and create a branch

   git checkout -b feat/get-market-hot-path-cache

2. Implement changes
   • contracts/predictify-hybrid/src/markets.rs
   • contracts/predictify-hybrid/src/storage.rs
3. Test and commit
   • cargo test -p predictify-hybrid markets -- --nocapture
   • Cover edge cases: cache miss, cache hit, cache invalidation
   • Include test output and notes in the PR

Example commit message

feat: hot-path cache for get_market with explicit invalidation

Acceptance Criteria

• Cache invalidated on every write
• TTL bumps explicit
• No unwrap() introduced
• Benchmarks show read-path improvement

Guidelines

• Avoid stale reads at all costs
• Minimum 95% coverage
• Clear documentation and inline comments
• Timeframe: 96 hours

[wavyboy-build]

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Hello maintainer, i would love to contribute to this repo

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[grantfox-oss]

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Next steps:

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