Code Requires Refactoring

There is a lot of duplicated code in `PluginProcessor.cpp`. Try creating functions and increase modularity.

Start by reading PluginProcessor.cpp and identify the duplicated sections and their shared responsibilities. Check how the processor is used by the JUCE VST3 audio plugin before deciding what can be extracted safely. Done means the duplication is reduced through functions or clearer modular boundaries without changing the plugin's behavior.

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