docs: remove OPERATIONS.md to separate PR per scope feedback

Moving OPERATIONS.md to separate PR #89 to keep PR #88 focused on
ElasticSearch documentation and comprehensive variable examples.

Addresses PR #88 comment PRRT_kwDOJnJ_Ds5Y9vRp regarding scope.

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: drernie