v2.6.7: Simplify Callbacks

This release of GOCART v2.6 has some changes to simplify callbacks looking toward the transition to MAPL3

This is zero-diff to v2.6.6

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Changed

• Introduce new function to add fields to callback state and reference field when retrieving by long name, attribute logic was unneccessary
• Update components.yaml to match that of GEOSgcm main as of 2026-09-30
  • ESMA_env v5.25.2
  • ESMA_cmake v4.49.1
  • ecbuild geos/v3.15.2
  • GMAO_Shared v3.0.2
  • MAPL v2.71.0
• Update CI to latest workflows and add ifx

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What's Changed

• Simplify callback field creation and access by @bena-nasa in #480
• v2.6: Prepare for 2.6.7 release, update CI by @mathomp4 in #483
• GitFlow: Merge release/v2.6 into main for 2.6.7 release by @mathomp4 in #484

Full Changelog: v2.6.6...v2.6.7