fix(inFilter): Enable inFilter usage with strings

[thaddeusdiamond]

Commit Message

commit 8a4418443ca4da09781dc8c91117cc0f19e1c298 (HEAD -> main, origin/main, origin/HEAD)
Author: Thaddeus Diamond
Date:   Sun May 18 00:34:10 2025 -0500

[Purpose]
Enable inFilter in test environments when the filter is a string.

[Technical]
- Strip quotations passed from client side HTTP call (e.g., PostgREST)
- Add unit testing to validate

[ Testing: flutter test ]

What kind of change does this PR introduce?

Bug fix

What is the current behavior?

Unit tests for string filters in Flutter code like this fail:

final response = await _client
        .from('my_table')
        .select()
        .inFilter('filter_col', ['filter val 1', 'filter val 2']);

What is the new behavior?

Strip (left and right) double quotations passed across HTTP wire.

Additional context

See unit tests