CODICE l2 metadata updates

[lacoak21]

Change Summary

closes #3311

Overview

These changes were outlined by Jon and the CoDICE team.

1. Fix DISPLAY_TYPE metadata
   • Change DISPLAY_TYPE from time_series to spectrogram for all CoDICE L2 variables that are 2-dimensional. Currently some files (e.g., hi-omni) already do this correctly; others (e.g., lo files) still say time_series, which makes CAVA plot them as line plots instead of spectrograms. Straightforward, mechanical fix.
2. Fix uncertainty variable handling
   • Uncertainties are currently defined as standalone/"free-floating" data variables, which makes them show up as separate plottable variables in CAVA (confusing). Instead, each uncertainty variable should be:
     • Marked VAR_TYPE: support_data (not data)
     • Attached to its parent variable via DELTA_PLUS_VAR / DELTA_MINUS_VAR pointing to the uncertainty variable name (e.g., unc_{species}) hi-omni already follows this pattern; lo-species and likely others need to be updated to match.

File changes

Update cdf attribute yaml files

[jtniehof]

#3293 might have fixed the RtD build

[jtniehof]

LGTM. I haven't thrown test files at CAVA or anything, but that's consistent with metadata that plots successfully.

[davidt0x]

LGTM