Added match function to the backend

[wpfl-dbt]

Context

Top of the features shopping list and vital for replicating the existing Company Matching endpoint using Matchbox is match().

Given an ID in a source dataset, it should return the paired keys from the target dataset from the perspective of a point of truth.

While there's plenty of edge cases and ways we might extend this, this is the vanilla implementation so we have something to work with.

Changes proposed in this pull request

• Adds match() as a function throughout the library: client, server base class, PostgreSQL adapter
• Adds simple unit tests based on identifying "Revolution Inc" across the warehouse data
• Adds indices to Clusters and Contains to facilitate speed on this query
• Modifies batch_ingest() to permit use of indices via a new isolate_table function
• Adds some helper function to visualise the data subgraph -- I used them to help me debug and felt they were useful enough to leave in
• Minor change to Models.get_lineage_to_dataset(): the dataset model is now also returned, with accompanying change in query() logic

Guidance to review

Focus on matchbox.server.postgresql.utils.query -- this is where the biggest, most confusing changes are.

• My unit tests lack some coverage. I don't have any examples of simple 1:1 because my source data has no examples of this. I think this is okay for now -- do you agree?
  • Note 1:0 is now covered
• I chose to implement the IDs as sets rather than str | list[str] | None because I think it's more elegant
• "Source" and "target" aren't language used elsewhere in the system, but I think it's justified as this is a reasonably unique operation for the system. Do you agree with this language?
• I considered implementing the API out of scope. Do you agree?

Relevant links

• Feature shopping list
• Matchbox in the CDL, where this function was ideated

Checklist:

• My code follows the style guidelines of this project
• New and existing unit tests pass locally with my changes

[lmazz1-dbt]

I agree that the API endpoint is out of scope, but I'd like to see more tests

[wpfl-dbt]

I agree that the API endpoint is out of scope, but I'd like to see more tests

Added 1:0 coverage as discussed.