feat(modifiers): bundle preset activations on profiles + editor Presets tab

Profiles can now carry a list of PresetActivation entries alongside
their per-type / per-instance modifiers. When such a profile is
picked in the Lobby, its bundled presets are unioned with any
layout suggestedPresets (profile config wins on id-collision).

Changes:

- ModifierProfile.presetActivations added (optional readonly array).
  Zod schema + server wire schema mirror the field; drift guard
  picks up forgotten updates on either side.
- ModifierProfileEditor grows a Presets tab in the right column
  sharing space with the Library tab. Each preset row carries a
  checkbox, scope radio (both/white/black), and a turns counter
  (blank = permanent). Inline diagnostics warn on redundant layout
  overlap and on loose-scope incompatibility; hard errors under
  overlapping scope disable Save.
- Lobby merges profile.presetActivations into its active preset
  set on profile select, on editor close, and on URL deep-link.
- LayoutPicker suggested-preset chips now expose aria-pressed so
  the active state is readable by assistive tech + e2e tests.

Tests: library round-trip preserves presetActivations (unit); two
new e2e scenarios (pre-seeded bundled profile auto-activates; full
editor-author loop persists + reflects in the lobby). 1752 unit +
105 playwright all green.

packages/chess/e2e/profile-layout-binding.spec.ts

@@ -158,6 +158,101 @@ test.describe('Modifier profile ⇄ layout binding', () => {
     ).toHaveCount(0);
   });
 
+  test('profile with bundled presetActivations auto-activates them in the Lobby', async ({
+    page,
+  }) => {
+    await freshLobby(page);
+    // Seed a profile bound to the pawns-only layout (which suggests
+    // first-promotion-wins) AND bundling that same preset. This lets
+    // us verify the chip flips to active purely from the profile
+    // selection — no user-tap on the suggested-preset chip involved.
+    await page.evaluate(
+      ({ key }) => {
+        const entry = {
+          id: 'lib-with-preset',
+          name: 'FPW Profile',
+          profile: {
+            id: 'lib-with-preset',
+            name: 'FPW Profile',
+            description: '',
+            layoutId: 'pawns-only',
+            perType: [],
+            perInstance: [],
+            presetActivations: [
+              {
+                id: 'first-promotion-wins',
+                scope: 'both',
+                turnsRemaining: null,
+              },
+            ],
+            version: 1,
+            source: 'custom',
+          },
+          starred: false,
+          updatedAt: Date.now(),
+        };
+        localStorage.setItem(key, JSON.stringify([entry]));
+      },
+      { key: PROFILE_LIBRARY_KEY },
+    );
+    await page.reload();
+
+    await page.getByTestId('profile-picker').selectOption('lib-with-preset');
+
+    // Layout auto-snaps to pawns-only (layoutId binding, already
+    // covered elsewhere but confirmed here for precondition).
+    await expect(page.getByTestId('layout-picker')).toHaveValue('pawns-only');
+
+    // The layout's suggested-preset chip for first-promotion-wins
+    // should now be pressed because the profile's
+    // presetActivations entry populated the Lobby's `presets` state.
+    const chip = page.getByTestId(
+      'layout-suggested-preset-first-promotion-wins',
+    );
+    await expect(chip).toBeVisible();
+    await expect(chip).toHaveAttribute('aria-pressed', 'true');
+  });
+
+  test('editor bundles a preset on save, which auto-activates on reselect', async ({
+    page,
+  }) => {
+    await freshLobby(page);
+
+    // Open the editor via the picker's "Custom…" option.
+    await page.getByTestId('profile-picker').selectOption('custom');
+    await expect(page.getByTestId('modifier-editor-modal')).toBeVisible({
+      timeout: 3000,
+    });
+
+    // Set name, bind the pawns-only layout, switch to the Presets tab.
+    await page.getByTestId('profile-name').fill('Bundled Presets Test');
+    await page.getByTestId('bound-layout-picker').selectOption('pawns-only');
+    await page.getByTestId('right-tab-presets').click();
+    await expect(page.getByTestId('preset-panel')).toBeVisible();
+
+    // Toggle the first-promotion-wins preset on.
+    await page
+      .getByTestId('preset-panel-toggle-first-promotion-wins')
+      .check();
+    // Scope defaults to "both" (the toggle button exposes aria-checked).
+    await expect(
+      page.getByTestId('preset-panel-scope-first-promotion-wins-both'),
+    ).toHaveAttribute('aria-checked', 'true');
+
+    // Save + close.
+    await page.getByTestId('save-profile').click();
+    await page.keyboard.press('Escape');
+
+    // Back in the lobby: the suggested-preset chip for the bundled
+    // rule shows as pressed because the editor-close handler applied
+    // the profile's bundled presets to the Lobby's active set.
+    const chip = page.getByTestId(
+      'layout-suggested-preset-first-promotion-wins',
+    );
+    await expect(chip).toBeVisible();
+    await expect(chip).toHaveAttribute('aria-pressed', 'true');
+  });
+
   test('editor persists the bound layout on save', async ({ page }) => {
     await freshLobby(page);