update for redisvl 0.19.0

[github-actions]

update for redisvl 0.19.0

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Note

Low Risk
Documentation-only changes to RedisVL API and user guides; no application or security logic is modified.

Overview
Documentation is updated for RedisVL 0.19.0 in two areas.

The Query API reference for VectorQuery drops epsilon from the constructor, parameter docs, set_epsilon(), and the epsilon property. KNN vector search docs no longer describe that runtime knob on VectorQuery; range-style epsilon remains on VectorRangeQuery in the same doc set.

The vectorizers how-to adds Ollama as a supported provider (install via redisvl[ollama], OllamaTextVectorizer, sync/async batch embed), broadens prerequisites to local model servers, and uses try/except so examples skip cleanly when Ollama is unavailable.

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[jit-ci]

🛡️ Jit Security Scan Results

✅ No security findings were detected in this PR

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^{Security scan by Jit}