feat(canopy-web): program-specific action handlers (TANF work-activity, WIC nutritional risk, CAPS authorization)

Source: worker-portal-expansion plan Follow-up Work.

The view-layer for TANF/Medicaid/CAPS/WIC tabs landed via worker-portal-expansion, but action handlers for those programs do not exist in canopy-web. Caseworkers can read TANF work-requirement state but cannot record a new work activity from the portal — they have to hit the canopy-tanf API directly.

Scope:

• TANF: log work activity, record exemption, update time-limit clock.
• WIC: create nutritional risk assessment, assign food package.
• CAPS: provider authorization workflow.
• Each handler follows the existing SNAP action pattern (htmx-targeted POST → upstream service → tab refresh).