refactor: story titles to Domein/<Context>/<Name>; add 2 missing stories (RD-04)

Three dashboard-section stories used a fourth title segment
(`Domein/Registratie/Dashboard/<Name>`) that the sidebar rule does not have.
Drop the `Dashboard/` segment so all story titles follow the one rule from
CLAUDE.md decision 5.

Add the two missing stories for sections that have more than one visual
state: `wat-moet-ik-regelen` (4 states) and `wat-wilt-u-doen` (2 states, the
first story in the new `Domein/Overzicht/` bucket). `beheer-links` gets no
story — it has one visual state and its other branch renders nothing.

The `MetTaken` story disables the a11y addon with the same reason and WP-11
reference already used on `task-list.stories.ts` and `choice-list.stories.ts`:
`app-choice-link`'s host sits between the keuzelijst `<ul>` and its `<li>`,
a pre-existing structural gap this ticket does not fix.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/ssp/src/app/overzicht/ui/wat-wilt-u-doen.section.stories.ts

@@ -0,0 +1,28 @@
+import type { Meta, StoryObj } from '@storybook/angular';
+import { applicationConfig } from '@storybook/angular';
+import { provideRouter } from '@angular/router';
+import { WatWiltUDoenSection } from './wat-wilt-u-doen.section';
+import { FeatureFlagStore } from '@shared/application/feature-flags.store';
+
+const meta: Meta<WatWiltUDoenSection> = {
+  title: 'Domein/Overzicht/Wat Wilt U Doen',
+  component: WatWiltUDoenSection,
+  decorators: [applicationConfig({ providers: [provideRouter([])] })],
+};
+export default meta;
+type Story = StoryObj<WatWiltUDoenSection>;
+
+export const InschrijvingOpen: Story = {
+  decorators: [
+    applicationConfig({
+      providers: [{ provide: FeatureFlagStore, useValue: { enabled: () => true } }],
+    }),
+  ],
+};
+export const InschrijvingDicht: Story = {
+  decorators: [
+    applicationConfig({
+      providers: [{ provide: FeatureFlagStore, useValue: { enabled: () => false } }],
+    }),
+  ],
+};