Create a "Getting Started" guide, including the process of installation of `opentf`

[RLRabinowitz]

The new documentation website should include a "Getting Started" guide, that would explain how to start using opentf

The guide should include instructions for installation, and how to quickstart using opentf. The installation section should also include how to verify the artifacts

I will create a separate comment here, detailing what should be part of the "verification" section

[RLRabinowitz]

For the verification of artifacts, the following should be done:

Verification of artifact checksums: The checksum file should be verified using cosign

cosign verify-blob \
  --certificate-identity 'https://github.com/opentofu/opentofu/.github/workflows/release.yml@refs/tags/vX.X.X' \
  --certificate-oidc-issuer 'https://token.actions.githubusercontent.com' \
  --cert 'https://github.com/opentofu/opentofu/releases/download/vX.X.X/opentofu_X.X.X_SHA256SUMS.pem' \
  --signature 'https://github.com/opentofu/opentofu/releases/download/vX.X.X/opentofu_X.X.X_SHA256SUMS.sig' \
  ./opentofu_X.X.X_SHA256SUMS

Verification of docker images: The docker images should be verified using cosign

cosign verify \
  --certificate-identity 'https://github.com/opentofu/opentofu/.github/workflows/release.yml@refs/tags/vX.X.X' \
    --certificate-oidc-issuer 'https://token.actions.githubusercontent.com' \
  the-image

[ghost]

Hey @RLRabinowitz I believe this is done. Can I close it?