feat: add 80-question kbase evaluation test suite

Add config/kbase_tests.yaml with 80 questions whose answers come from
kbase articles (Solutions + Articles) in OKP. All source documents are
post-January 2025 (after Gemini 2.5 Flash cutoff).

Purpose: Demonstrate the value of having kbase content in search_portal
by comparing correctness with and without kbase suppression.

Topics covered: containers, storage, security/crypto, networking,
virtualization, identity/auth, kernel/boot, upgrades/migration,
package management, subscriptions, HA clustering, cloud, and more.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Author: Lifto