🔒 Fix application crash on unhandled Symbol properties in proxies

[johnstrand]

🎯 What: Fixed a vulnerability in createStore proxies (usePending and useSquawk) where arbitrary symbol properties were being mistakenly added to internal state trackers, causing potential application crashes.

⚠️ Risk: If a system accessing these proxies (like a debugging tool, a React internal mechanism, or malicious code) attempts to read a Symbol off of them, the symbol was improperly tracked as a string context. This would cause downstream string manipulations on the context tracker to fail catastographically, taking down the frontend application.

🛡️ Solution: Modified the get trap in both usePending and useSquawk proxies to only register the property in the context tracker if (typeof prop === "string"). Non-string property accesses (like Symbols) simply return the value normally without attempting to track them. Includes accompanying unit tests for safety.

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PR created automatically by Jules for task 14356909526467052655 started by @johnstrand

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