refactor(ssr): Phase 3 — full Selmer migration of Transaction Bulk Code; remove the wizard

Migrates the Transaction Bulk Code modal (a single-step form wearing a full
wizard costume) to a plain Selmer form, cold-applying the ssr-form-migration
skill. Almost entirely reuse of the Phase-2 work: the whole `sc/*` Selmer
component library, `account-typeahead*` / `location-select*`, and the
`edit-modal` / `transitioner` chrome are imported wholesale.

What changed
- Wizard removed: deleted `BulkCodeWizard` / `AccountsStep` records,
  `MultiStepFormState`, the `step-params[...]` prefix, and all `mm/*`
  middleware. Replaced with a plain handler + flat `wrap-bulk-state` (decode
  straight into `bulk-code-schema`, no snapshot round-trip).
- Selection round-trip: the non-editable transaction selection is resolved to
  a concrete not-locked id vector at open and ridden back in hidden `ids[]`
  fields (the bulk analog of edit's single `db/id`) — no EDN snapshot, no
  filter re-query, and more correct (codes exactly the rows the user saw).
- 100% Selmer render path (only the shared terminal `com/success-modal` keeps
  Hiccup — heuristic-9 exception). New shared component `sc/select`
  (`location-select.html` generalized) for the status dropdown.
- Routes 4 -> 3: GET `bulk-code` (open), POST `bulk-code-submit`, POST
  `bulk-code-form-changed` (one whole-form op dispatcher folding the old
  `new-account` + `vendor-changed` routes). Location swap moved off `find *`
  onto explicit `#account-location-<index>` + `hx-select`.
- Fixed a latent correctness bug surfaced by the migration: the vendor
  typeahead needs `:id` (value-keyed `:key`) or its value-bound hidden goes
  stale across a whole-form swap and posts blank.

Scorecard delta (transaction/bulk_code.clj): mm coupling 19->0, snapshot
merges 4->0, wizard records 3->0, step-params 10->0, routes 4->3, OOB 0,
Hiccup-in-render ->0 (bar success-modal). LOC 420->506 (documented exception:
the wizard was a thin shell over mm/* defaults, so explicitness moves shared
plumbing into the file). Cookbook: reused the entire Phase-2 sc/* lib + chrome,
added sc/select.

Verification: bulk-code-transactions.spec.ts 13/13; full Playwright suite
39/39; cljfmt clean.

Skill fed: scorecard row + narrative + LOC exception; gotchas (value-bound
typeahead keying, selection-as-ids round-trip); cookbook (sc/select).

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

e2e/bulk-code-transactions.spec.ts

@@ -40,7 +40,7 @@ async function openBulkCodeModal(page: any) {
   const codeButton = page.locator('button:has-text("Code")').first();
   await codeButton.click();
   await page.waitForSelector('#modal-holder[x-show="open"]', { state: 'visible' });
-  await page.waitForSelector('#wizardmodal');
+  await page.waitForSelector('#bulkcodemodal');
 }
 
 async function closeBulkCodeModal(page: any) {
@@ -156,7 +156,7 @@ async function addNewAccount(page: any) {
 }
 
 async function submitBulkCodeForm(page: any) {
-  const form = page.locator('#wizard-form');
+  const form = page.locator('#bulk-code-form');
   await form.evaluate((el: HTMLFormElement) => {
     el.dispatchEvent(new Event('submit', { bubbles: true }));
   });
@@ -184,7 +184,7 @@ test.describe('Bulk Code Transactions - Happy Path', () => {
     await expect(page.locator('text=Bulk editing 1 transactions')).toBeVisible();
     
     // Select vendor
-    const vendorHidden = page.locator('input[type="hidden"][name="step-params[vendor]"]').first();
+    const vendorHidden = page.locator('input[type="hidden"][name="vendor"]').first();
     const testInfo = await getTestInfo(page);
     await vendorHidden.evaluate((el: HTMLInputElement, value: string) => {
       const newInput = document.createElement('input');
@@ -196,7 +196,7 @@ test.describe('Bulk Code Transactions - Happy Path', () => {
     await page.waitForTimeout(300);
     
     // Select approval status
-    const statusSelect = page.locator('select[name="step-params[approval-status]"]').first();
+    const statusSelect = page.locator('select[name="approval-status"]').first();
     await statusSelect.selectOption('approved');
     
     // Add account
@@ -278,7 +278,7 @@ test.describe('Bulk Code Transactions - Validation', () => {
     const testInfo = await getTestInfo(page);
     const vendorId = testInfo.accounts.vendor;
     
-    const vendorContainer = page.locator('div[hx-post*="vendor-changed"]').first();
+    const vendorContainer = page.locator('div[hx-vals*="vendor-changed"]').first();
     const vendorHidden = vendorContainer.locator('input[type="hidden"]').first();
     
     await vendorHidden.evaluate((el: HTMLInputElement, value: string) => {
@@ -293,11 +293,11 @@ test.describe('Bulk Code Transactions - Validation', () => {
       el.dispatchEvent(new Event('change', { bubbles: true }));
     });
     
-    await page.waitForResponse(response => response.url().includes('/vendor-changed') && response.status() === 200);
+    await page.waitForResponse(response => response.url().includes('/form-changed') && response.status() === 200);
     await page.waitForTimeout(500);
     
     // Select approval status
-    const statusSelect = page.locator('select[name="step-params[approval-status]"]').first();
+    const statusSelect = page.locator('select[name="approval-status"]').first();
     await statusSelect.selectOption('approved');
     
     // Vendor selection pre-populated a default account row at 100%.
@@ -310,11 +310,15 @@ test.describe('Bulk Code Transactions - Validation', () => {
     // Modal should still be open
     await expect(page.locator('#modal-holder[x-show="open"]')).toBeVisible();
     
-    // Vendor should still be selected
-    const vendorHiddenAfter = page.locator('input[type="hidden"][name="step-params[vendor]"]').first();
-    const vendorValueAfter = await vendorHiddenAfter.inputValue();
-    expect(vendorValueAfter).toBe(vendorId.toString());
-    
+    // Vendor should still be selected. The vendor typeahead is Alpine-managed and posts
+    // its value via an x-bound hidden input, so the right correctness check is what the
+    // form actually submits (the value that gets saved), not the lagging DOM .value of the
+    // hidden read in isolation.
+    await expect.poll(async () =>
+      page.locator('#bulk-code-form').evaluate((f: HTMLFormElement) =>
+        new FormData(f).get('vendor'))
+    ).toBe(vendorId.toString());
+
     // Status should still be selected
     const statusValueAfter = await statusSelect.inputValue();
     expect(statusValueAfter).toBe('approved');
@@ -464,7 +468,7 @@ test.describe('Bulk Code Transactions - Vendor Pre-population', () => {
     
     // The vendor typeahead dispatches change from its parent div
     // We need to set the hidden input and dispatch change on the container
-    const vendorContainer = page.locator('div[hx-post*="vendor-changed"]').first();
+    const vendorContainer = page.locator('div[hx-vals*="vendor-changed"]').first();
     const vendorHidden = vendorContainer.locator('input[type="hidden"]').first();
     
     await vendorHidden.evaluate((el: HTMLInputElement, value: string) => {
@@ -481,7 +485,7 @@ test.describe('Bulk Code Transactions - Vendor Pre-population', () => {
     });
     
     // Wait for HTMX response
-    await page.waitForResponse(response => response.url().includes('/vendor-changed') && response.status() === 200);
+    await page.waitForResponse(response => response.url().includes('/form-changed') && response.status() === 200);
     await page.waitForTimeout(500);
     
     // Account should be pre-populated - check for account row
@@ -521,7 +525,7 @@ test.describe('Bulk Code Transactions - Vendor Pre-population', () => {
     const testInfo = await getTestInfo(page);
     const vendorId = testInfo.accounts.vendor;
     
-    const vendorContainer = page.locator('div[hx-post*="vendor-changed"]').first();
+    const vendorContainer = page.locator('div[hx-vals*="vendor-changed"]').first();
     const vendorHidden = vendorContainer.locator('input[type="hidden"]').first();
     
     await vendorHidden.evaluate((el: HTMLInputElement, value: string) => {
@@ -538,7 +542,7 @@ test.describe('Bulk Code Transactions - Vendor Pre-population', () => {
     });
     
     // Wait for HTMX response
-    await page.waitForResponse(response => response.url().includes('/vendor-changed') && response.status() === 200);
+    await page.waitForResponse(response => response.url().includes('/form-changed') && response.status() === 200);
     await page.waitForTimeout(500);
     
     // Should pre-populate the vendor's default account (non-clientized) plus the "New account" row