Add vendor pre-population for bulk code and individual edit forms

- Add vendor-changed HTMX handlers for both bulk code and individual edit
- Pre-populate default account at 100% when vendor is selected and no accounts exist
- Fix render-accounts-section to render from step-params correctly
- Change bulk code vendor-changed from hx-get to hx-post to include form data
- Add routes for vendor-changed endpoints
- Update e2e tests to cover vendor pre-population
- Run lein cljfmt fix across codebase

src/cljc/auto_ap/routes/pos/sales_summaries.cljc

@@ -2,7 +2,7 @@
 (def routes {""       {:get ::page
                        :put ::edit-wizard-submit}
              "/table" ::table
-             ["/" [#"\d+" :db/id]] {:get ::edit-wizard }
+             ["/" [#"\d+" :db/id]] {:get ::edit-wizard}
              "/edit/navigate"           ::edit-wizard-navigate
              "/edit/sales-summary-item"  ::new-summary-item
              "/edit/item-account"       ::edit-item-account