⚡ Bolt: [performance improvement] Optimize fs.readFileSync Memory Allocation

[vishnu-madhavan-git]

💡 What
Replaced usages of fs.readFileSync(filepath).toString() with fs.readFileSync(filepath, 'utf8') across @expo/cli, @expo/config-plugins, expo-brownfield, and pod-install.

🎯 Why
When fs.readFileSync is called without an encoding argument, it returns a raw Buffer. Calling .toString() on this buffer allocates a new string in memory and copies the data over. By directly passing 'utf8' as the encoding to fs.readFileSync, Node.js decodes the file contents directly into a string, bypassing the intermediate Buffer allocation, saving memory and reducing garbage collection overhead.

📊 Impact
Minor but consistent memory and CPU usage improvements during CLI operations, project building, and templating where file reading happens synchronously, due to reduced memory allocation and garbage collection.

🔬 Measurement
No functional change, memory profiling on node scripts running these functions should show fewer Buffer allocations.
Passed lint and test suites on modified packages (@expo/cli, @expo/config-plugins, expo-brownfield, pod-install).

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PR created automatically by Jules for task 209893582691112827 started by @vishnu-madhavan-git

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Project	Deployment	Actions	Updated (UTC)
nexlyn	Error		Apr 7, 2026 8:09am

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