docs: add guide for DBConvert Streams integration

[slotix]

This adds a "Replicate data from Neon" guide for DBConvert Streams, a self-hosted tool that
reads changes from Postgres via logical decoding and applies them to another database. It
runs as a desktop app on Windows, macOS, or Linux, or in Docker on a server, so replicated
rows go from Neon straight to the destination without passing through a third-party service.
Its SQL IDE is free and connects to Neon directly, so a reader can browse schemas and query
their Neon database without setting up replication at all; the migration and CDC engine is
the paid part.

It follows the structure of the existing vendor guides in this series (Stacksync, Decodable,
Estuary Flow), and registers the page the same way:

• content/docs/guides/logical-replication-dbconvert-streams.md — the guide
• content/docs/navigation.yaml — sidebar entry under Replicate from Neon, alphabetical
• content/docs/guides/integrations.md — TechCards entry
• public/images/technology-logos/dbconvert-streams.svg — logo
• src/config/docs-icons-config.js — regenerated with generate-docs-icons-config.js

The guide covers enabling logical replication, creating a dedicated replication role,
granting schema access, creating the publication, and configuring the connection and CDC
stream on the DBConvert Streams side. It reuses the standard admonitions for the
irreversible wal_level change and for compute/billing, and it notes that a direct
(non-pooler) connection string is required.

Screenshots are from a real Neon → MySQL CDC run against a neondb database, with
credentials and the operator's IP masked. The logical-replication step reuses the existing
neon-console-settings-logical-replication.png rather than adding another console asset.

Formatting verified with Prettier.

Happy to adjust the framing, trim scope, or split anything out — just say what you'd prefer.

[vercel]

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