feat: when a value is pasted or any other string is typed, default to equals (#43611)

## I have read the
[CONTRIBUTING.md](https://github.com/supabase/supabase/blob/master/CONTRIBUTING.md)
file.

YES

## What kind of change does this PR introduce?

Right now when users type a value or paste a value after selecting a
column on the new filter bar, it kinda just fails. This just allows them
to default to equals and continue


https://github.com/user-attachments/assets/6af52c1d-3f6a-4bdb-8e22-61d7e5a756ae

e2e/studio/features/filter-bar.spec.ts

@@ -371,6 +371,38 @@ test.describe('Filter Bar', () => {
       }
     })
 
+    test('Enter on equals fallback applies filter and returns focus to freeform', async ({
+      page,
+      ref,
+    }) => {
+      const tableName = `${tableNamePrefix}_op_default_equals`
+      const columnName = 'name'
+
+      await createTable(tableName, columnName, [{ name: 'forgecode' }, { name: 'other' }])
+
+      try {
+        await setupFilterBarPage(page, ref, toUrl(`/project/${ref}/editor?schema=public`))
+        await navigateToTable(page, ref, tableName)
+
+        await selectColumnFilter(page, columnName)
+
+        const operatorInput = page.getByTestId(`filter-operator-${columnName}`)
+        await operatorInput.fill('forgecode')
+
+        await expect(page.getByText('Equals: "forgecode"')).toBeVisible()
+
+        const rowsWaiter = createApiResponseWaiter(page, 'pg-meta', ref, 'query?key=table-rows-')
+        await page.keyboard.press('Enter')
+        await rowsWaiter
+
+        await expect(getFilterBarInput(page)).toBeFocused()
+        await expect(page.getByRole('gridcell', { name: 'forgecode' })).toBeVisible()
+        await expect(page.getByRole('gridcell', { name: 'other' })).not.toBeVisible()
+      } finally {
+        await dropTable(tableName)
+      }
+    })
+
     test('Backspace on empty operator removes condition', async ({ page, ref }) => {
       const tableName = `${tableNamePrefix}_op_bksp`
       const columnName = 'name'