fix: don't require embedding model in case astra db token lacks perms

[erichare]

This pull request addresses permission issues with Astra DB Application Tokens that may lead to unexpected behavior in the Astra DB Component. Specifically:

1. It does not explicitly require providing an Embedding Model - at runtime, the error will alert the user if one is required for non-vectorize collections
2. It handles the scenario where a user has multiple databases, but a token scoped to a single database, in which the app will be unable to load collection information about the database. Now, the component will skip the unscoped database(s) and correctly load information about the DBs that the token are scoped to.
3. It updates the Vector Store RAG template to use the newest version of the component, and has been verified to correctly operate with Vectorize collections.

[codspeed-hq]

CodSpeed Performance Report

Merging #5926 will improve performances by ×24

_{Comparing fix-astradb-vectorize (89a33de) with main (5c64e59)}

Summary

⚡ 1 improvements
✅ 8 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_successful_run_with_input_type_any	4,163.7 ms	170.6 ms	×24