This commit resolves the issue where `pg_isready` would fail when
`socketDir` is set and `listen_addresses` is empty. `pg_isready` is now
modified to leverage `socketDir` when it is available.
* Added option depends_on which will be useful to append extra depends_on configuration to the <name>-init process.
* more meaningful `depends_on` option's description
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Co-authored-by: shivaraj-bh <sbh69840@gmail.com>
* Use psql instead of postgres, as a result, use `pg_ctl` to temporarily start the postgres server in `${name}-init` process.
* Avoid creating a custom `postgresPkg` with extensions by using `apply` attribute provided by `mkOption`
* Refactor setup script, use `writeShellApplication` and resolve shell-check errors
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Co-authored-by: shivaraj-bh <sbh69840@gmail.com>
