fix(projects): require a pericope set before the Import tab can submit (#420)

The tab enabled Create Project without one while the modal refused the
submit silently, so the button lit up and did nothing. A project cannot exist
without a pericope set, so the rule now matches the field's required marker.

Claude-Session: https://claude.ai/code/session_014fMrwRFHtdtJCL3QrvRFSJ

Author: henrique221

src/features/projects/components/UsfmImportTab.test.tsx

@@ -25,6 +25,7 @@ const COMPLETE_FORM: ProjectFormData = {
   sourceLanguage: 1,
   sourceBible: 10,
   targetLanguage: 2,
+  pericopeSetId: 1,
 };
 
 /** jsdom's File has no usable `text()`, so the component's read path needs one supplied. */
@@ -206,7 +207,14 @@ describe('UsfmImportTab fields after validation (#420)', () => {
     expect(screen.getByRole('button', { name: 'createProject' })).toBeDisabled();
   });
 
-  it('enables Create Project once title, source bible and target language are set', async () => {
+  it('keeps Create Project disabled without a pericope set, since the modal would refuse it', async () => {
+    renderTab({ formData: { ...COMPLETE_FORM, pericopeSetId: null } });
+    drop([usfmFile('gen.usfm', GEN)]);
+    await waitFor(() => expect(screen.getByText('createProject')).toBeInTheDocument());
+    expect(screen.getByRole('button', { name: 'createProject' })).toBeDisabled();
+  });
+
+  it('enables Create Project once title, source bible, target language and pericope set are set', async () => {
     renderTab({ formData: COMPLETE_FORM });
     drop([usfmFile('gen.usfm', GEN)]);
     await waitFor(() => expect(screen.getByText('createProject')).toBeInTheDocument());

src/features/projects/components/UsfmImportTab.tsx

@@ -96,13 +96,15 @@ export function UsfmImportTab({
   };
 
   /**
-   * #420's rule, which is not the New tab's: Book(s) comes from the files rather than a picker,
-   * and Pericope Set is not part of it.
+   * #420's rule plus the pericope set: Book(s) comes from the files rather than a picker, and a
+   * project cannot exist without a pericope set, so the button must not light up before one is
+   * chosen — the modal would only refuse the submit silently.
    */
   const canSubmit =
     Boolean(formData.title.trim()) &&
     Boolean(formData.sourceBible) &&
     Boolean(formData.targetLanguage) &&
+    Boolean(formData.pericopeSetId) &&
     accepted.length > 0;
 
   // Before any file is accepted the tab is only the upload area; afterwards it is replaced by the