fix: support python 3.14 in various projects

[cbornet]

Support Python 3.14 in:

• standard-tests
• text-splitters
• langchain-classic
• lib/partners except:
  • chroma: lib onnxruntime not compatible atm
  • huggingface: lib pytorch not compatible atm
  • nomic: lib pyarrow not compatible atm

Not in this PR:

• langchain-core: done in fix(core): support for Python 3.14 #33461
• langchain-cli: currently broken (see Broken dependencies in langchain-cli #33458)
• langchain_v1: test_injected_state_in_middleware_agent() not passing in CI (but passing locally...)

[codspeed-hq]

CodSpeed Performance Report

Merging #33477 will not alter performance

_{Comparing cbornet:all-py314 (e08429a) with master (41fe18b)¹}

Summary

✅ 17 untouched
⏩ 17 skipped²

Footnotes

1. No successful run was found on master (9140a7c) during the generation of this report, so 41fe18b was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 17 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩