feat: add DOM-TOM country codes and auto-detect mobile prefixes during registration

[clemPerrousset]

This commit adds the DOM-TOM territories to the country selection list in CountryCode.swift using their respective country names and codes, but with the French flag (🇫🇷) as requested. It also enhances Utils.validatePhoneFormat(countryCode:phone:) to automatically detect specific DOM-TOM mobile prefixes (e.g., 0690, 0696, 0692) when the user selects France (+33) or leaves the country code blank. The correct regional prefix (e.g., +590, +596, +262) is automatically applied and formatted.

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PR created automatically by Jules for task 1899077492698153567 started by @clemPerrousset

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