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* origin/v5: (25 commits)
  chore(providers/langchain): extract to separate package (#5928)
  Version Packages (canary) (#5898)
  fix (docs): fix typo (#5914) (#5919)
  docs: update chat-with-pdf page to include updated provider information (#5895) (#5917)
  docs: Added documentation for function call parsing middleware (#5900)
  refactoring: extract SharedV2Headers (#5912)
  feat (providers/openai): add support for reasoning summaries (#5906) (#5909)
  fix (docs): fix OpenRouter code examples (#5876) (#5893)
  fix(providers/xai): return actual usage when streaming instead of NaN (#5873) (#5891)
  fix (docs): fix valibotSchema import (#5865) (#5889)
  fix (providers/fal): improve model compatibility (#5855) (#5892)
  chore: extract spec types (#5901)
  chore: remove logprobs (#5896)
  Version Packages (canary) (#5872)
  chore (ci): unify jobs & remove unnecessary example builds (#5894)
  feat (ai): allow using provider default temperature by specifying null (#5890)
  fix(ai/mcp-stdio): make `createChildProcess` synchronous to prevent spawn race condition (#5852) (#5888)
  feat (providers/google): add thinking config to provider options (#5842) (#5887)
  fix (examples): avoid mixed message types in `use-chat-streamdata-multistep` (#5824) (#5886)
  chore: restructure language model supported urls (#5882)
  ...