🐛 fix logic of parsing multiple columns (i.e. for PRIMARY KEYS, CONSTRAINT)

[Shion1305]

Description

This PR is a partial fix for issue #192.

Bug Descriptions:

• The current logic fails to parse multiple columns in PRIMARY KEY expressions (e.g., PRIMARY KEY (column1, column2)).
• It does not properly recognize certain column names, such as column,1.

Changes Introduced

• This PR addresses the first bug by improving the logic for parsing multiple columns within parentheses.
• The parseAllColumns function is now capable of correctly parsing column names, even when they are escaped, like ("column""1").

Additional Notes:

The second bug (handling of column names with commas) will be addressed in a separate PR, which is still in progress.

Reference

SQLite implements its escaping logic as follows:
https://github.com/sqlite/sqlite/blob/cf25c16a54f68d1ca095b91bd0ead840578b2bb4/ext/fts3/fts3.c#L464-L486

• Do only one thing
• Non breaking API changes
• Tested

User Case Description

Refer test cases.

[Shion1305]

@jinzhu Hi! Is there any change you could review this PR? Thanks in advance 🙏