Confirm: comped CE fees count as org subsidy in the revenue report

The problem

A CE fee can only ever end up in one of three places: paid, comped (a discount allocation), or owed. #2072 made "paid" and "owed" real figures on the events revenue report — but nothing claimed the comped slice, so a fully-discounted CE fee was neither collected nor outstanding and disappeared from the report entirely.

Example — a $60 CE fee comped in full:

The middle column is the hole: $60 of value the org gave away, invisible on every figure.

What we did

Counted CE discounts as org subsidy, matching how a discounted registration fee is already treated. Net and total expected drop by the comped amount. Implemented in EventRevenueFigures (app/services/event_revenue_figures.rb) — it's the one place the batched report figures deliberately diverge from EventDashboard.

What needs confirming

• Is "the org gave away $60" the right read of a comped CE fee for annual-report purposes? (The alternative is treating CE comps as never-was-revenue, i.e. leaving them out of every bucket — which is what was happening by accident.)
• Should the same reasoning extend to a partially comped CE fee ($60 fee, $20 discount, $40 paid → $20 subsidy)? That's what the code does today; flagging it because it wasn't discussed separately.
• Does the revenue page need to show CE discounts broken out from registration discounts, or is one combined "Discounts" line enough?

Context

• Introduced by #2072
• app/services/event_revenue_figures.rb — discount_cents sums Discount allocations across both EventRegistration and ContinuingEducationRegistration
• spec/services/event_revenue_report_spec.rb — "discounted CE fees" describes the expected accounting
• CE comps are reachable in the UI today: the allocations page for a CE registration (app/views/continuing_education_registrations/_payment_history.html.erb) has an "Add discount" action

Review app/services/event_revenue_figures.rb and the discounted CE fees example in spec/services/event_revenue_report_spec.rb, then compare the existing registration discount treatment with the CE allocation flow in app/views/continuing_education_registrations/_payment_history.html.erb. Confirm the accounting treatment for full and partial CE discounts and whether the revenue page needs separate discount lines; done means the policy is agreed and the report behavior and tests match it.