refactor: general improvements and cleanup in policy components

[MichaelSteinert]

This PR cleans up the policy components, improves template safety, and fixes several residuals from the assets view.
Changes:

• Safety & Cleanup: Replaced unsafe non-null assertions (!) with optional chaining (?.) in templates and removed redundant null checks.
• Typo Fixes: Corrected test names, error alerts, and JSDocs that mistakenly referenced "assets" instead of "policies".
• UI: Replaced the hardcoded pagination count with a dynamic pageItemCount.
• Config: Removed unused path mappings in tsconfig.json.

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