refactor: implement rapidfuzz

[rmfranken]

Proposed Changes

Implementing rapidfuzz matcher (return only 1 IRI for a string, if rapidfuzz finds a match above score 90).
Add tests.
Add logging so you can see in the terminal which labels were IRIfied, which can help you pick a better match threshold.

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Further Comments

[Copilot]

Pull Request Overview

This PR implements rapidfuzz fuzzy string matching functionality to the RDF transformer, enabling approximate matching when exact matches are not found. The changes add configurable fuzzy matching with a threshold-based scoring system to improve string-to-IRI mapping capabilities.

Key changes:

• Added rapidfuzz dependency and fuzzy matching logic to RDFTransformer
• Enhanced API endpoint to accept fuzzy matching parameters (fuzzy flag and threshold)
• Updated tests to validate both exact and fuzzy matching scenarios

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

File	Description
pyproject.toml	Adds rapidfuzz>=3.0.0 dependency
src/strings2things/app/core/rdf_transformer.py	Implements fuzzy matching with configurable threshold and refactors matching logic
src/strings2things/app/api/endpoints.py	Updates API to accept fuzzy matching parameters and creates transformer instances per request
tests/test_rdf_transformer.py	Adds comprehensive test coverage for exact, fuzzy, and no-match scenarios

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