docs: add self-hosted Supabase deployment guide

[jumski]

This pull request adds documentation for deploying pgflow on self-hosted Supabase instances. The changes include:

• Added a new self-hosted Supabase deployment guide covering Postgres image upgrades, database connection configuration, and manual Edge Function deployment
• Updated the deployment index page to include a link to the self-hosted guide alongside the existing Supabase.com guide
• Enhanced the database connection documentation with a note about self-hosted instances requiring explicit EDGE_WORKER_DB_URL configuration
• Added cross-references between the main Supabase deployment guide and the new self-hosted guide
• Standardized quote usage from double quotes to single quotes throughout the affected documentation files

The new guide addresses key differences in self-hosted deployments including the need for pgmq 1.5.0+, manual environment variable configuration, and alternative deployment methods since the Supabase CLI only works with Supabase.com.

[jumski]

• docs: add self-hosted Supabase deployment guide #619 👈 (View in Graphite)
• main

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[changeset-bot]

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Latest commit: 2ece426

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[nx-cloud]

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☁️ Nx Cloud last updated this comment at 2026-03-23 09:07:50 UTC

[github-actions]

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✅ Deployment successful!

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📝 Details:

• Branch: 03-23-self-hosted_supabase_guidde
• Commit: 2b7a69ac0fde234084927da6093ff9947ab93f64
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