langchain-perplexity 1.4.2

Changes since langchain-perplexity==1.4.1

release(perplexity): 1.4.2 (#41392) chore(model-profiles): refresh model profile data (#41354) chore(deps): bump certifi from 2025.8.3 to 2026.10.19 in /libs/partners/perplexity (#41377) fix(perplexity): preserve Agent API search results (#41349) fix: fix dependencies in some partner packages (#41266) chore(deps): bump urllib3 from 2.7.0 to 2.8.0 in /libs/partners/perplexity (#40947) chore(deps): bump anyio from 4.11.0 to 4.14.2 in /libs/partners/perplexity (#40633) fix(perplexity): map Responses API cache tokens into input_token_details (#39923) fix(perplexity): emit search_context_size once per stream in _astream (#39924) docs(perplexity): update ChatPerplexity docstring examples for Agent API (#39831)