Phone number should save and return raw one

(Need further discussions)

Instead of normalising every phone no. at the output, it seems better to take the phone number as raw text, and output as raw text, instead of currently normalize as E.164.

We should still use E.164 as uniqueness checking and validation.

Start by reviewing the existing phone-number normalization, validation, and uniqueness-checking paths. Clarify the expected behavior for storing and returning raw text while retaining E.164 checks, then confirm the scope and acceptance criteria through the requested discussion before attempting implementation.

Written by the indexing model from the issue text.