expose diagnostics frequency and reduction for each component

[juliasloan25]

Purpose

With this change, we can output hourly instantaneous diagnostics of each component (and the coupler fields), which will hopefully facilitate debugging CMIP. When we use these higher frequency diagnostics, they should be visible while the simulation is still running and also afterwards even if the simulation crashes.

Closes #1650

Content

• add config options for land and coupler diagnostics period and reduction
• updated CMIP longrun configs to output daily instantaneous diagnostics
• add hourly diagnostics to the two CMIP runs in regular CI so this feature gets tested (and decrease sim lengths)
• added tests for new helper functions
• bugfix: pass output_dir to CL.default_diagnostics so we call the model-specific method rather than the no-op default

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