refactor(ssr): Phase 4 — full Selmer migration of POS Sales Summary; remove the wizard; fix add-item + totals

Migrates the POS Sales Summary edit modal off the wizard to a plain Selmer form,
building on the parity gate committed earlier. Largest migration so far and the
first with no prior test coverage.

What changed
- Wizard removed: deleted MainStep/EditWizard records, MultiStepFormState, the
  step-params[...] prefix, the EDN snapshot round-trip, and all mm/* middleware.
  Replaced with a plain handler + flat wrap-decode/wrap-derive-state. The 51 fc/
  cursor refs are de-cursored into explicit data + Selmer templates.
- db/id-keyed item merge: wrap-derive-state overlays posted items onto the
  persisted items by :db/id, so read-only fields the form doesn't post
  (ledger-side, amount) survive a re-render and the debit/credit split + totals
  stay correct. New manual rows (temp db/id) ride through as-is.
- Inline click-to-edit account cell preserved as three small targeted
  .account-cell-swap routes (edit/save/cancel-item-account), ported to Selmer
  with the new field-name scheme.
- 100% Selmer modal render path (the remaining Hiccup / hx-swap-oob / "hx-"
  strings are all grid-page code — grid render lambdas, the filters form, and the
  submit response-header map — not the modal).
- Routes: dropped edit-wizard-navigate + new-summary-item; added form-changed.

Fixes (two pre-existing bugs, per request)
- "New Summary Item" add button (was throwing `newRowIndex is not defined` and
  targeting a non-existent `.new-row`) is now a whole-form-swap op=new-item that
  adds an editable manual row (category + account typeahead + debit/credit money
  inputs + remove).
- The dead totals/balance display (malformed Hiccup that discarded its labels) is
  replaced by a proper #summary-totals block showing running Total +
  Balanced/Unbalanced, refreshed via a Rule-4 targeted swap on manual amount edits.

Scorecard delta (pos/sales_summaries.clj): LOC 790->732, mm coupling 20->0,
wizard records 4->0, fc/ cursor 51->0, step-params 27->0 (2 comments), modal
routes 8->6. (hx-swap-oob 1 and mixed-hx live in the grid page, not the modal.)

Verification: sales-summary spec 7/7 (incl. the two fixes); full Playwright suite
46/46; cljfmt clean. Skill fed: scorecard row + narrative; gotchas (parity-gate-
first, characterize-then-fix, keyup-trigger tests); cookbook (inline click-to-edit
cell, db/id-keyed item merge).

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

e2e/sales-summary-edit.spec.ts

@@ -45,11 +45,12 @@ test.describe('Sales Summary Edit (characterization)', () => {
     expect(await modal.locator('[hx-get*="edit/item-account"]').count()).toBe(2);
   });
 
-  test('seeded summary is balanced (no out-of-balance indicator)', async ({ page }) => {
+  test('seeded summary is balanced (shows Balanced totals, no out-of-balance)', async ({ page }) => {
     await openEditModal(page);
     const modal = page.locator('#wizardmodal');
-    // balanced: $500 debit == $500 credit, so no unbalanced warning text
-    await expect(modal).not.toContainText('Out of balance');
+    // balanced: $500 debit == $500 credit -> the (now-fixed) totals block shows Balanced
+    await expect(modal.locator('#summary-totals')).toContainText('Balanced');
+    await expect(modal.locator('#summary-totals')).toContainText('$500.00');
     await expect(modal).not.toContainText('Unbalanced');
   });
 
@@ -92,22 +93,36 @@ test.describe('Sales Summary Edit (characterization)', () => {
     await expect(display.locator('[hx-get*="edit/item-account"]')).toBeVisible();
   });
 
-  // NOTE: the "New Summary Item" button is currently BROKEN in this modal and is
-  // therefore intentionally not characterized as working. Its Alpine handler
-  // (`@click="$dispatch('newRow', {index: (newRowIndex++)})"`) throws
-  // "newRowIndex is not defined" (the modal's x-data is empty), and even if it
-  // fired, `hx-target="closest .new-row"` matches no ancestor in this div layout,
-  // so the `new-summary-item` route never fires. We assert the *current* behavior:
-  // the button is present but adds nothing. The migration may fix or preserve this.
-  test('New Summary Item button is present but currently inert (documents the break)', async ({ page }) => {
+  // The "New Summary Item" button was broken in the pre-migration wizard (its Alpine
+  // handler threw "newRowIndex is not defined"); the migration fixes it as a whole-form
+  // swap (op=new-item). This asserts the FIXED behavior: clicking adds an editable manual
+  // row (category + account typeahead + debit/credit money inputs).
+  test('New Summary Item adds an editable manual row (fixed)', async ({ page }) => {
     await openEditModal(page);
     const modal = page.locator('#wizardmodal');
-    const before = await modal.locator('input').count();
-    await modal.locator('[hx-get*="sales-summary-item"]').first().click();
-    await page.waitForTimeout(500);
-    // no manual row was added (no category input appeared, input count unchanged)
-    expect(await modal.locator('input[placeholder="Category/Explanation"]').count()).toBe(0);
-    expect(await modal.locator('input').count()).toBe(before);
+    expect(await modal.locator('.manual-item-row').count()).toBe(0);
+
+    await modal.locator('a[hx-vals*="new-item"]').click();
+    await expect(modal.locator('.manual-item-row').first()).toBeVisible();
+    expect(await modal.locator('.manual-item-row').count()).toBe(1);
+
+    const row = modal.locator('.manual-item-row').first();
+    await expect(row.locator('input[placeholder="Category/Explanation"]')).toBeVisible();
+    expect(await row.locator('input[name*="[debit]"]').count()).toBe(1);
+    expect(await row.locator('input[name*="[credit]"]').count()).toBe(1);
+  });
+
+  test('a manual debit amount recomputes the totals to Unbalanced (fixed)', async ({ page }) => {
+    await openEditModal(page);
+    const modal = page.locator('#wizardmodal');
+    await expect(modal.locator('#summary-totals')).toContainText('Balanced');
+    await modal.locator('a[hx-vals*="new-item"]').click();
+    await expect(modal.locator('.manual-item-row').first()).toBeVisible();
+    // adding a $500 debit -> $1000 debit vs $500 credit -> the totals block recomputes
+    const debit = modal.locator('.manual-item-row input[name*="[debit]"]').first();
+    await debit.click();
+    await debit.pressSequentially('500');  // fires keyup -> hx-trigger "keyup changed delay:300ms"
+    await expect(modal.locator('#summary-totals')).toContainText('Unbalanced', { timeout: 5000 });
   });
 
   test('Save closes the modal and the summary stays in the grid', async ({ page }) => {