WASM size optimization pipeline with reported budget

[ayshadogo]

User Story:
As a developer, I want WASM binaries optimized and their size tracked in CI so that deployment costs stay predictable.

Acceptance Criteria:

• wasm-opt -Oz integrated into the release build pipeline; optimized WASM used for all deployments
• Pre- and post-optimization sizes reported as a CI artifact on every build
• A documented size target (under 100KB per contract) with the build failing, or at minimum loudly warning, if a contract exceeds it — explain in docs/deployment.md what to do if a legitimate feature pushes past the budget
• docs/deployment.md also covers Testnet/Mainnet deployment steps, required environment variables, initialization steps, and troubleshooting for common deploy errors

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