Fix crash in URL constructor when URL has hash but no protocol

[Nedunchezhiyan-M]

Summary

Fix a crash in the URL constructor when parsing URLs that contain a # but no :// separator (e.g., mailto:user@example.com#section).

The code splits on :// and accesses index [1] without checking if it exists, then calls .includes('/') on undefined, causing a TypeError.

Changelog:

[GENERAL] [FIXED] - Fix crash in URL constructor when URL contains hash but no protocol separator

Test Plan

1. Create a URL with new URL('mailto:user@example.com#section') - should not throw
2. Added unit test to verify URLs with hash but no :// don't crash
3. Existing URL tests continue to pass

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