feat(projects): list + create API and creatable ProjectAutocomplete (T4)

- GET /api/projects returns the shared global list; POST /api/projects
  creates a project, deduped case-insensitively (F3).
- Repository find-or-create trims and matches on lower(name); a unique index
  on lower(name) enforces the same rule at the DB (replacing the case-
  sensitive column unique constraint) — migration 0001.
- ProjectAutocomplete: creatable autocomplete that lists projects, offers to
  create an unknown name inline, and selects it without reload.
- Integration test (dedupe/list against Postgres) + component test.

tests/project-autocomplete.nuxt.spec.ts

@@ -0,0 +1,93 @@
+// @vitest-environment nuxt
+import { describe, it, expect, beforeEach, vi } from 'vitest'
+import { mountSuspended, registerEndpoint } from '@nuxt/test-utils/runtime'
+import { flushPromises } from '@vue/test-utils'
+import { defineEventHandler, readBody } from 'h3'
+import ProjectAutocomplete from '../app/components/ProjectAutocomplete.vue'
+
+interface Row {
+  id: string
+  name: string
+}
+
+let store: Row[]
+
+beforeEach(() => {
+  store = [
+    { id: '1', name: 'Acme' },
+    { id: '2', name: 'Globex' },
+  ]
+  // One endpoint backing both list (GET) and creatable autocomplete (POST),
+  // deduping case-insensitively like the real API.
+  registerEndpoint(
+    '/api/projects',
+    defineEventHandler(async (event) => {
+      if (event.method === 'GET') return store
+      const { name } = await readBody<{ name: string }>(event)
+      const trimmed = name.trim()
+      const existing = store.find(
+        (p) => p.name.toLowerCase() === trimmed.toLowerCase(),
+      )
+      if (existing) return existing
+      const created = { id: String(store.length + 1), name: trimmed }
+      store.push(created)
+      return created
+    }),
+  )
+})
+
+describe('ProjectAutocomplete', () => {
+  it('lists the existing projects when opened', async () => {
+    const wrapper = await mountSuspended(ProjectAutocomplete)
+    await flushPromises()
+
+    await wrapper.find('[data-test="project-input"]').trigger('focus')
+    const names = wrapper
+      .findAll('[data-test="project-option"]')
+      .map((el) => el.text())
+    expect(names).toContain('Acme')
+    expect(names).toContain('Globex')
+  })
+
+  it('offers to create a project that does not exist yet', async () => {
+    const wrapper = await mountSuspended(ProjectAutocomplete)
+    await flushPromises()
+
+    const input = wrapper.find('[data-test="project-input"]')
+    await input.setValue('Initech')
+    expect(wrapper.find('[data-test="project-create"]').exists()).toBe(true)
+  })
+
+  it('does not offer to create a name that already exists (case-insensitive)', async () => {
+    const wrapper = await mountSuspended(ProjectAutocomplete)
+    await flushPromises()
+
+    await wrapper.find('[data-test="project-input"]').setValue('acme')
+    expect(wrapper.find('[data-test="project-create"]').exists()).toBe(false)
+  })
+
+  it('persists a new project, selects it, and makes it selectable without reload', async () => {
+    const wrapper = await mountSuspended(ProjectAutocomplete)
+    await flushPromises()
+
+    await wrapper.find('[data-test="project-input"]').setValue('Initech')
+    await wrapper.find('[data-test="project-create"]').trigger('click')
+
+    // Selected and emitted to the parent (the POST resolves asynchronously).
+    await vi.waitFor(() => {
+      expect(wrapper.emitted('update:modelValue')).toBeTruthy()
+    })
+    await flushPromises()
+    const emitted = wrapper.emitted('update:modelValue')!
+    expect(emitted.at(-1)![0]).toMatchObject({ name: 'Initech' })
+
+    // Persisted to the store and now selectable without reload — reopening the
+    // list (the create flow closes it) shows the new project.
+    expect(store.map((p) => p.name)).toContain('Initech')
+    await wrapper.find('[data-test="project-input"]').trigger('focus')
+    const names = wrapper
+      .findAll('[data-test="project-option"]')
+      .map((el) => el.text())
+    expect(names).toContain('Initech')
+  })
+})