Setup Codeflash Github Actions to optimize all future code

[aseembits93]

• This Pull Request sets up the codeflash.yml file which will run on every new Pull Request that modifies the source code for unstructured-ingest directory.
• We setup the codeflash config in the pyproject.toml file. This defines basic project config for codeflash.
• Please take a look at the requirements that are being installed. Feel free to add more to the install list. Codeflash tries to execute code and if it is missing a dependency needed to make something run, it will fail to optimize.
• Codeflash is being installed everytime in the CI. This helps the workflow always use the latest version of codeflash as it improves rapidly. Feel free to add codeflash to dev dependency as well, since we are about to release more local optimization tools like VS Code and claude code extensions.
• Feel free to modify this Github action anyway you want
  Actions Required to make this work-
• Install the Codeflash Github app from this link to this repo. This is required for our github-bot to comment and create suggestions on the github repo.
• Create a new CODEFLASH_API_KEY after signing up to Codeflash from our website. The onboarding will ask you to create an API Key and show instructions on how to save the api key on your repo secrets.
  Then, after this PR is merged in it will start generating new optimizations 🎉

[potter-potter]

this uv sync line may cause a pretty big install. lets keep an eye on it

[potter-potter]

assuming we need nltk.downloader as a requirement for unstructured?

[potter-potter]

looks good

we may need the version and changelog.. we will find out