docs(website): drop manual-install instructions for delete_flow_and_data

[jumski]

Summary

• The Delete Flow and its Data guide told users to install pgflow.delete_flow_and_data manually by pasting the function SQL.
• The function ships in pgflow migrations (pkgs/core/schemas/0100_function_delete_flow_and_data.sql) since v0.10.0, so the manual-install caution aside, the "Installing the Function" section, and the embedded SQL listing were stale.
• Replaced them with a version note: built-in helper, installed automatically by pgflow migrations, available since v0.10.0, no manual SQL setup. The danger aside, usage example, "After Deleting", and "See Also" sections are unchanged.

Checks

• pnpm --filter @pgflow/website build passes (135 pages, internal links valid).
• Pre-commit and pre-push hooks pass (prevent-commit-on-main, validate-changesets, nx affected prepush).
• @pgflow/website is in the changesets ignore list, so no changeset is needed for this docs-only change.

Fixes #608

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☁️ Nx Cloud last updated this comment at 2026-09-04 20:59:33 UTC

[jumski]

Merge activity

• Sep 4, 8:57 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Sep 4, 8:58 PM UTC: Graphite rebased this pull request as part of a merge.
• Sep 4, 9:00 PM UTC: @jumski merged this pull request with Graphite.

[jumski]

• docs(website): drop manual-install instructions for delete_flow_and_data #668 👈 (View in Graphite)
• main

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[github-actions]

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[github-actions]

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✅ Deployment successful!

🔗 Preview URL: https://pr-668.pgflow.pages.dev

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• Branch: issue-608-docs2
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