Validate caching implementation and measure performance improvements

Description

Test the complete Docker build caching implementation by running multiple staging builds and measuring performance improvements to ensure the 40% build time reduction target is achieved

Acceptance Criteria

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• #1 First build after cache implementation runs successfully (expected slower due to cache population),Second and subsequent builds show significant time reduction compared to baseline,Build time reduction of at least 40% is achieved and documented,GitHub Actions minutes consumption is reduced compared to baseline measurements,All Docker images function identically to pre-optimization builds,No build failures or regressions are introduced by caching changes

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