[AGENT] Fix docs deploy environment wiring

[BASIC-BIT]

Summary

• point Terraform GitHub provider management at Chronote-gg/Chronote so Actions environment variables are written to the live repo
• add docs deploy preflight checks in production and staging workflows to fail fast when DOCS_BUCKET or DOCS_DISTRIBUTION_ID is missing or inaccessible
• update the Terraform PAT rotation instructions in README.md for the current org and repository

Validation

• terraform fmt \"_infra/main.tf\"
• terraform -chdir=\"_infra\" init -backend=false
• terraform -chdir=\"_infra\" validate
• npx markdownlint-cli2 \"README.md\"
• npx prettier --check \".github/workflows/deploy.yml\" \".github/workflows/deploy-staging.yml\" \"README.md\"

Notes

• Root cause appears to be stale Terraform GitHub provider targeting the old BASIC-BIT/meeting-notes-discord-bot repository, which would leave docs deploy environment vars out of sync in Chronote-gg/Chronote.

[BASIC-BIT]

[AGENT] Superseded by #163. I rechecked the fix against current \master\ and it is still relevant, but this branch was based on unrelated feature work, so it carries noisy history and merge conflicts that are not worth preserving. The clean replacement branch contains only the current docs deploy wiring fix.