test(e2e): align specs with current page structure

join-flow:
- Form now requires Community Guidelines agreement; tests check the
  checkbox before expecting submit to enable.
- Contribution input is a numeric field with preset chip buttons, not a
  USelect with $0/mo options — fill the input directly.
- Success state lives in SignupFlowOverlay ("Welcome to Ghost Guild!");
  no .success-box exists. Match by heading instead.
- Inline .error-box renders OUTSIDE <form>, so duplicate-email assertion
  uses .signup-flow-overlay .error-box (which is the user-facing error).

member-profile:
- "How you appear to other members" copy was retired; replace with the
  stable "Show in Member Directory" structural label.
- Add waitForLoadState('networkidle') after goto for ClientOnly auth
  hydration so "Edit Profile" reliably appears within timeout.

board:
- Add waitForLoadState('networkidle') after goto so the action-bar's
  "+ New Post" click handler is bound before the test clicks.
- Submit button is named exactly "Post" — disambiguate from "+ New Post"
  buttons with { exact: true }.
- Delete is a two-step in-card confirm (Delete → Confirm), not a native
  browser dialog; drop the page.once('dialog') listener.

admin-board-channels:
- Channel name placeholder is "e.g., coop-formation" (no leading #).
- Slack Channel ID input only appears in the Edit modal (v-if="editingId"),
  not on Create — Slack channel is auto-created server-side. Drop the
  slack ID fill from the Create step.
- Add waitForLoadState('networkidle') before opening the modal.

e2e/board.spec.js

@@ -9,6 +9,7 @@ test.describe('Board page', () => {
 
   test('clicking New Post reveals the form', async ({ memberPage }) => {
     await memberPage.goto('/board')
+    await memberPage.waitForLoadState('networkidle')
     await expect(memberPage.getByRole('button', { name: '+ New Post' }).first()).toBeVisible({
       timeout: 15000,
     })
@@ -40,6 +41,7 @@ test.describe('Board page', () => {
 
   test('create, edit, and delete own post', async ({ memberPage }) => {
     await memberPage.goto('/board')
+    await memberPage.waitForLoadState('networkidle')
     await expect(memberPage.getByRole('button', { name: '+ New Post' }).first()).toBeVisible({
       timeout: 15000,
     })
@@ -55,7 +57,7 @@ test.describe('Board page', () => {
     await memberPage.locator('#post-title').fill(originalTitle)
     await memberPage.locator('#post-seeking').fill('Playwright test seeking text')
 
-    await memberPage.getByRole('button', { name: 'Post' }).click()
+    await memberPage.getByRole('button', { name: 'Post', exact: true }).click()
 
     await expect(memberPage.getByRole('heading', { name: originalTitle })).toBeVisible({
       timeout: 10000,
@@ -75,10 +77,10 @@ test.describe('Board page', () => {
       timeout: 10000,
     })
 
-    // --- Delete (confirm dialog) ---
-    memberPage.once('dialog', (dialog) => dialog.accept())
+    // --- Delete (in-card two-step confirm; not a native dialog) ---
     const editedCard = memberPage.locator('article.board-post', { hasText: editedTitle })
     await editedCard.getByRole('button', { name: 'Delete' }).click()
+    await editedCard.getByRole('button', { name: 'Confirm' }).click()
 
     await expect(memberPage.getByRole('heading', { name: editedTitle })).not.toBeVisible({
       timeout: 10000,