refactor(ssr): full Selmer migration of Transaction Edit; remove the wizard

Squashed Phase-2 SSR work: migrate the Transaction Edit modal's render path
entirely to Selmer templates (zero Hiccup in the render path), rip out the
multi-step wizard abstraction (EditWizard/LinksStep records, MultiStepFormState,
step-params[...] field names, mm/* middleware) in favor of a plain form with
flat derived state, and promote shared UI components to reusable Selmer partials
under resources/templates/components/. Adds the Selmer interop bridge, the
auto-ap.ssr.components.selmer (sc) wrapper library, and the ssr-form-migration
skill capturing the learnings.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/cljc/auto_ap/routes/transactions.cljc

@@ -1,7 +1,6 @@
 (ns auto-ap.routes.transactions)
 
 (def routes {"" {:get ::page
-                 :put ::edit-wizard-navigate
                  "/unapproved" ::unapproved-page
                  "/requires-feedback" ::requires-feedback-page
                  "/approved" ::approved-page
@@ -28,13 +27,8 @@
 
              ["/" [#"\d+" :db/id]] {"/edit" {:get ::edit-wizard}}
              "/edit-submit" ::edit-submit
-             "/edit-vendor-changed" ::edit-vendor-changed
              "/location-select" ::location-select
-             "/account-total" ::account-total
-             "/account-balance" ::account-balance
-             "/toggle-amount-mode" ::toggle-amount-mode
-             "/edit-wizard-new-account" ::edit-wizard-new-account
-             "/edit-wizard-toggle-mode" ::edit-wizard-toggle-mode
+             "/edit-form-changed" ::edit-form-changed
              "/match-payment" ::link-payment
              "/match-autopay-invoices" ::link-autopay-invoices
              "/match-unpaid-invoices" ::link-unpaid-invoices