docs(aggregate.md): clarify objectsLimit/certainty usage

[bevzzz]

The docs now stress that vector search reranks objects, not filters them

What's being changed:

Type of change:

• Documentation updates (non-breaking change to fix/update documentation)
• Website updates (non-breaking change to update main page, company pages, pricing, etc)
• Content updates – blog, podcast (non-breaking change to add/update content)
• Bug fix (non-breaking change to fixes an issue with the site)
• Feature or enhancements (non-breaking change to add functionality)

How Has This Been Tested?

• GitHub action – automated build completed without errors
• Local build - the site works as expected when running yarn start

note, you can run yarn verify-links to test site links locally

[orca-security-eu]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	SAST	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca

[g-despot]

Thanks for your contribution, sounds so much better now 🥳

[orca-security-eu]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	SAST	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca