Exclude/Hide Databases via Environment Variable or Bookmark

[helldrum]

Hello pgweb team !

I would like to propose a new feature for pgweb: the ability to exclude or hide specific databases from being displayed, either via an environment variable or through a bookmark
configuration.

Currently, there is no straightforward mechanism to control database visibility directly from pgweb's configuration (or I don't find it in the documentation).
This feature would be highly beneficial in environments where pgweb is deployed centrally and where there is a need to:

• Enhance security: Restrict the visibility of sensitive databases for certain users or environments.
• Simplify the user interface: Hide internal or temporary databases that are not relevant to the end-user.
• Improve deployment management: Allow dynamic and simplified configuration of database visibility without modifying the application itself.
  Proposed Implementation:

1. Via an Environment Variable:

• Add an environment variable such as PGWEB_EXCLUDE_DATABASES (or PGWEB_IGNORE_DATABASES) that would accept a list of database names (separated by commas or another delimiter)
  to be hidden.
• Example: PGWEB_EXCLUDE_DATABASES=template0,template1,postgres_internal

2. Via Bookmark Configuration (.toml):

• Add a new key to the bookmark.toml file, for example, exclude_databases = ["postgres", "cloudsqladmin"].
  This feature would offer valuable flexibility for pgweb administration and usage in various contexts.
  Thank you for considering this suggestion.

Regards,
Helldrum