20260309 ada chart fixes

[som-sewardr1]

Ticket Link #fill_in

Remove if not applicable

Description

Added discovery-ui chart support for LINK_COLOR (link_color) to allow overriding the brand default link color. (Largely for ADA compliance reasons.)

Reminders

• Did you up the relevant chart version numbers? (If appropriate)
  • If you up a chart version within urban-os, have you also upped the urban-os chart version itself?
  • If charts within the urban-os chart (andi, etc) have been updated, have you run helm dependency updateh in /charts/urban-os and commited the Chart.lock file?
• Does helm template . -f values.yaml pass? (Checks for default values provided in chart and catches other errors)
• Do you have git hooks installed? (See README.md to install)
• If global values were altered, are they included as chart default values?
  • Are they also specified in the urbanos chart values file?
• If references to external charts were added:
  • Was the github release action updated to helm update {new_thing} it's dependencies?
  • Was the deploy repo -u flag updated to helm update {new_thing} to ensure it's not left out of deployments?

[rseward]

Code changes appear fit for purpose.