⚡ Bolt: Add in-memory manifest cache to LocalStorageThemeCache

[himattm]

💡 What: Added a lightweight in-memory cache layer (manifestCache) to LocalStorageThemeCache for the wasmJs target to track the keys array.
🎯 Why: LocalStorageThemeCache previously parsed the JSON manifest array from localStorage on every operation (e.g. size(), keys(), put(), evict()), which is very expensive when done repeatedly.
📊 Impact: Significantly reduces execution time and overhead for all cache operations by avoiding unnecessary JSON decoding, particularly important in a single-threaded WebAssembly browser environment.
🔬 Measurement: Execute ./gradlew :halogen-engine:wasmJsBrowserTest to ensure no functionality is broken. Performance improvement can be observed in reduced CPU usage and faster operation response times.

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PR created automatically by Jules for task 12436222383997282008 started by @himattm

[google-labs-jules]

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[himattm]

Closing as superseded by #35, which is the latest cleaned LocalStorageThemeCache manifest-cache optimization merged to main. Keeping one canonical implementation avoids merging multiple generated variants of the same change.

[google-labs-jules]

Closing as superseded by #35, which is the latest cleaned LocalStorageThemeCache manifest-cache optimization merged to main. Keeping one canonical implementation avoids merging multiple generated variants of the same change.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.