Migrate transitive PostgreSQL dependencies (jackc/pgconn) to jackc/pgx/v5 ecosystem

[tk-l2002]

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Ory Network Project

No response

Describe the bug

Note: This is a dependency/maintenance issue, not a runtime bug.

Currently, ory/hydra relies on ory/popwhich pulls in github.com/jackc/pgconn and github.com/jackc/pgproto3/v2 as transitive dependencies.

Both of these jackc packages have reached their End-of-Life on July 1, 2025.

In the newer versions of the jackc ecosystem, pgconn has been merged directly into the main pgx repository (github.com/jackc/pgx/v5/pgconn).

To ensure long-term stability and security, the dependency chain should be migrated to use github.com/jackc/pgx/v5.

Reproducing the bug

You can verify the presence of the deprecated packages by inspecting the Go module dependencies.
Run the following commands in the root of the hydra repository:

go mod why github.com/jackc/pgconn
go mod why github.com/jackc/pgproto3/v2

Relevant log output

Relevant configuration

Version

v26.2.0

On which operating system are you observing this issue?

None

In which environment are you deploying?

None

Additional Context

No response