Add version verification script/workflow

Write a script that examines the version in `META.json`, `pg_clickhouse.control`, `doc/pg_clickhouse.md`, and `CHANGELOG.md`, and the `$GITHUB_REF_NAME` environment variable (when `$CI` is set and it's a version) to ensure they're compatible. Things to check:

* The version in `META.json` is canonical. Both instances of it there should be the same
* The version in `pg_clickhouse.control` must be the same as the `x.y` part of the version from `META.json`
* Aside from `0.1`, the `x.y` part must always have an upgrade script in the sql directory
* If a workflow is running for a semantic version tag, the tag must be the same as the full `x.y.z` version from `META.json` version
* PG_MODULE_MAGIC must be the same full `x.y.z` version from `META.json`

Any violations should raise an error (or be automated away).

Start by examining META.json, pg_clickhouse.control, doc/pg_clickhouse.md, CHANGELOG.md, the sql directory, and the PG_MODULE_MAGIC definition to identify each version source. Account for CI and semantic version tags through CI and GITHUB_REF_NAME, then verify that every listed incompatibility raises an error or is automated away.

Written by the indexing model from the issue text.