* fix: preserve comma-separated values for flagged CLI arguments
The CLI argument parser was splitting all comma-separated values into
separate positional args before argparse could process them. This caused
multi-symbol queries like --symbol AAPL,MSFT,GOOGL to fail with
'args couldn't be interpreted' for all symbols after the first.
Flag values are now identified by checking whether the preceding token
is a known option string with nargs != 0, and their commas are preserved
so the provider receives the original comma-separated string.
* test: add coverage for comma-split fix in parse_known_args_and_warn
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Co-authored-by: Danglewood <85772166+deeleeramone@users.noreply.github.com>
* remove python 3.9 support and code
* black
* more cli lint
* more linting
* more lint
* fix for tests
* docstring grammar police
* add lock to to build function to avoid async import race conditions
* grammar police
* lots more linting
* relock