Feature request: trim all leading and trailing white space for all columns for all tables in a database

It's pretty common that i need to trim leading or trailing white space from lots of columns in a database a part of an initial ETL.

I use the following recipe a lot, and it would be great to include this functionality into sqlite-utils

trimify.sql

select 'select group_concat(''update [' || name || '] set ['' || name || ''] = trim(['' || name || ''])'', '';
'') || '';
'' as sql_to_run from pragma_table_info('''||name||''');' from sqlite_schema;

then something like:

	sqlite3 example.db < scripts/trimify.sql > table_trim.sql && \
             sqlite3 $example.db < table_trim.sql > trim.sql && \
             sqlite3 $example.db < trim.sql

Start by reviewing the trimify.sql recipe and the sqlite3 command pipeline described in the issue, then inspect sqlite-utils' existing CLI and database-operation entry points. Done means sqlite-utils provides a defined way to trim leading and trailing whitespace across all columns in all tables, with behavior verified against the example database workflow.