Add CSP customization methods and update config

[shgysk8zer0]

Introduces functions to customize Content Security Policy (CSP) sources and policies in csp.js, including methods to add sources and lock CSP arrays. Updates useCSP to handle empty arrays and errors gracefully. Reorders responsePostprocessors in http.config.js and updates package version to 1.0.3 in package.json and package-lock.json. Adds new export mappings in package.json.

Description and issue

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List of significant changes made