Update DBConvert Streams Hetzner tutorial

[slotix]

Summary

Updated the DBConvert Streams tutorial for transferring a database to Hetzner Cloud.

Changes include:

• Reworked the setup flow to install DBConvert Streams before attaching PostgreSQL to the internal Docker network
• Updated PostgreSQL deployment to avoid exposing port 5432 publicly
• Refreshed connection, stream configuration, monitoring, Compare, and Data Explorer screenshots
• Updated verification guidance to use DBConvert Streams Compare and Explorer views
• Added logical backup guidance alongside Hetzner snapshots

Notes

PostgreSQL now runs on the internal stream-net Docker network and is reached by DBConvert Streams through the container hostname postgres.

Testing

• Checked Markdown formatting with git diff --check
• Verified all referenced screenshots exist

[svenja11]

Thank you for the update @slotix!

[svenja11]

Please add the following comment and I will merge this PR (replace YOUR NAME <YOUR@EMAILPROVIDER.TLD> with your own information):

I have read and understood the Contributor's Certificate of Origin available at the end of
https://raw.githubusercontent.com/hetzneronline/community-content/master/tutorial-template.md
and I hereby certify that I meet the contribution criteria described in it.
Signed-off-by: YOUR NAME YOUR@EMAILPROVIDER.TLD

[slotix]

I have read and understood the Contributor's Certificate of Origin available at the end of
https://raw.githubusercontent.com/hetzneronline/community-content/master/tutorial-template.md
and I hereby certify that I meet the contribution criteria described in it.
Signed-off-by: Dmitry Narizhnykh streams@dbconvert.com