Isok -- a PostgreSQL extension for query based data integrity management

[Isok](https://kop.codeberg.page/pg_isok_docs/) is PostgreSQL extension for query based data integrity
management. It is now available for public testing.

Documentation and installation instructions:
[https://kop.codeberg.page/pg_isok_docs/](https://kop.codeberg.page/pg_isok_docs/)

Discover problematic data patterns, track them, and manage them, by
reporting not only the *existence* of particular data patterns, but also
by tracking *changes* to patterns of data and managing issue resolution.
When configured to accept some questionable rows but not others of the
same kind, Isok acts like a "soft trigger".

Useful for "zero code required" batch-based data validation. Most
useful when review is required to determine whether a questionable
data pattern should be allowed to remain in a database.

Although the core Isok code has been in production use for over a
decade, this release has enhanced features that have not been used in
production.

Isok can be built as pure SQL, for installation in the cloud or other
managed PostgreSQL instances.

Isok targets PostgreSQL 10 or later.