chore(community): allow Python 3.14, update deps

[mdrxy]

• Expand to permit Python 3.14
• Update dependencies

Temporary Dependency Removal

• google-cloud-bigquery (from 'bigquery' extra)
• google-cloud-documentai-toolbox (from 'docai' extra)

Due to upstream compatiblity issues with Python 3.13+

googleapis/python-documentai-toolbox#388
googleapis/python-documentai-toolbox#389
googleapis/python-bigquery#2316

Potentially breaking

For users who:

• Install with pip install langchain-google-community[bigquery]
• Install with pip install langchain-google-community[docai]
• Import BigQueryLoader or Document AI components directly

Workaround

pip install langchain-google-community
pip install google-cloud-bigquery>=3.21.0
pip install google-cloud-documentai-toolbox>=0.13.3a0  # if Python < 3.13

These dependencies will be restored once upstream fixes are available.

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Closes #1319