feat(defects): add shared arktype defect input schema

Shared validation source for the DefectForm and /api/defects route
(Task 5): trimmed non-empty sectionId/verbatim and a uuid projectId.

shared/schemas/defect.ts

@@ -0,0 +1,19 @@
+import { type } from 'arktype'
+
+/**
+ * The user-supplied fields when filing a defect. `reporterEmail` and the
+ * timestamp are resolved server-side (getReporter / DB default), so they are
+ * not part of this input. This is the single source of validation truth shared
+ * by the DefectForm and the /api/defects route (wired in Task 5); import it via
+ * the `#shared` alias from either client or server.
+ */
+export const defectInput = type({
+  // section_id comes from the clicked board section — a non-empty slug.
+  sectionId: type('string.trim').to('string >= 1'),
+  // projectId references projects.id, a uuid.
+  projectId: 'string.uuid',
+  // The reporter's words — required, trimmed.
+  verbatim: type('string.trim').to('string >= 1'),
+})
+
+export type DefectInput = typeof defectInput.infer

tests/defect-schema.spec.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from 'vitest'
+import { type } from 'arktype'
+import { defectInput } from '../shared/schemas/defect'
+
+const valid = {
+  sectionId: 'a4-flow',
+  projectId: '123e4567-e89b-12d3-a456-426614174000',
+  verbatim: 'The thing broke',
+}
+
+describe('defectInput schema', () => {
+  it('accepts a valid defect and trims verbatim', () => {
+    const out = defectInput({ ...valid, verbatim: '  hi  ' })
+    expect(out instanceof type.errors).toBe(false)
+    expect((out as typeof valid).verbatim).toBe('hi')
+  })
+
+  it('rejects empty verbatim', () => {
+    expect(defectInput({ ...valid, verbatim: '' }) instanceof type.errors).toBe(true)
+  })
+
+  it('rejects whitespace-only verbatim', () => {
+    expect(defectInput({ ...valid, verbatim: '   ' }) instanceof type.errors).toBe(true)
+  })
+
+  it('rejects a non-uuid projectId', () => {
+    expect(defectInput({ ...valid, projectId: 'not-a-uuid' }) instanceof type.errors).toBe(true)
+  })
+})