Workbench: pass only "enabled" args to a model run

[emilyanndavis]

Description

Fixes #2436.

Specifically: the Workbench now filters model args to include only those whose corresponding form fields are enabled at the time a model is run.

Example: Carbon model with sample datastack

Log, Before

Arguments for InVEST carbon 3.18.1.dev16+ga61b6b649.d20260304:
calc_sequestration        True
carbon_pools_path         /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/carbon_pools_willamette.csv
discount_rate             
do_valuation              False
lulc_alt_path             /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/lulc_future_willamette.tif
lulc_alt_year             2050
lulc_bas_path             /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/lulc_current_willamette.tif
lulc_bas_year             2020
n_workers                 -1
price_per_metric_ton_of_c 
rate_change               
results_suffix            willamette
workspace_dir             /Users/eadavis/invest-workspaces/carbon-disabled-inputs

Log, After

calc_sequestration True
carbon_pools_path  /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/carbon_pools_willamette.csv
do_valuation       False
lulc_alt_path      /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/lulc_future_willamette.tif
lulc_bas_path      /Users/eadavis/invest-inputs/invest-sample-data_3.17.2/Carbon/lulc_current_willamette.tif
n_workers          -1
results_suffix     willamette
workspace_dir      /Users/eadavis/invest-workspaces/carbon-disabled-inputs

Note the log now omits all args that are enabled only when do_valuation is True (namely: lulc_bas_year, lulc_alt_year, discount_rate, price_per_metric_ton_of_c, and rate_change).

Args Table, Before

Note the values listed for lulc_bas_year and lulc_alt_year.

Args Table, After

Note that None is now listed for lulc_bas_year and lulc_alt_year.

Checklist

• Updated HISTORY.rst and link to any relevant issue (if these changes are user-facing)
  - [ ] Updated the user's guide (if needed)
• Tested the Workbench UI (if relevant)

[claire-simpson]

Tested this locally and it looks good - thanks @emilyanndavis!