[mohamedzeidan2021]

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[github-actions]

🤖 AI code review

This is a routine release PR bumping the monorepo to 3.26.0 (sagemaker-core 2.26.0, sagemaker-train/serve/mlops 1.26.0). It updates VERSION files, internal dependency pins in all pyproject.toml files, and rolls up CHANGELOG entries. The changes are consistent across all five packages and match the established release mechanics (Source: #6310). No issues found.

_{Reviewed commit 9aa2587. Automated review; verify before acting.}