fix: Support new Postgres index API

[rorz]

Drizzle 0.31.0 introduced a breaking change to the Postgres indexes API. The lack of support in drizzle-dbml-generator for enriched "extra config" columns led to two failure scenarios with the current build:

1. Unrecognised ordering options in extra config e.g. tbl.f1.asc() (asc() not found in standard column type)
2. Inability for the underlying drizzle-orm calls to use the indexes. JSON parsing would fail since the defaultConfig on a given column wasn't being set or enriched.

What has changed

• Update drizzle-orm dev-dependency to the latest version (0.31.1)
• Extract richer / correct extra config for columns via a new ExtraConfigColumns symbol. This is specific to Postgres but functionally works in a dialect-agnostic way.
• Re-word extraConfig → extraConfigBuilder to make language clearer and more accurate
• Add some more tests for the new API

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resolves #12

[L-Mario564]

Thanks for the PR! I'll merge and create a new release later today