fix: cli.py not sending ALL_MESSAGES fix, walk-conversation, post db tests

[isandesh7]

cli was not sending all messages to load messages causing it to load only first message and if the first message did not have parts it did not load anything.

to verify i've added post db checks which load the most heavy conversation and outputs it result on the console in human readable format

Also had to add a pytest.ini to support console logs to be shown in default pytest commnd

I had made some fixes to load_document before observing the root cause.
I kept them since the tests are passing on those changes.

[Scarvy]

@isandesh7 Thanks for the PR!

Tests failed looking for the database in the new pytest file you added. See below:

platform linux -- Python 3.11.12, pytest-8.3.5, pluggy-1.5.0
rootdir: /home/runner/work/chatgpt-to-sqlite/chatgpt-to-sqlite
configfile: pytest.ini
collected 3 items

tests/test_chatgpt_to_sqlite.py::test_version PASSED
tests/test_post_import_sanity_on_db.py::test_preview_documents ERROR
tests/test_post_import_sanity_on_db.py::test_sanity_check_db FAILED

==================================== ERRORS ====================================
___________________ ERROR at setup of test_preview_documents ___________________
tests/test_post_import_sanity_on_db.py:[15](https://github.com/Scarvy/chatgpt-to-sqlite/actions/runs/14296529473/job/40895923771?pr=1#step:5:16): in get_most_active_conversation_with_messages
    cursor.execute(
E   sqlite3.OperationalError: no such table: conversations

I think adding a fixture to initialize a temporary database to run the sanity checks will fix it. After that it will be good to merge 👍.

[isandesh7]

@Scarvy I have added the fixture. The tests pass now.