Rename lists -> projects and items -> cards throughout

Project scope shifts from a todo list to a project-management app. This is a
straight terminology rename across code, comments, migrations, tests, and
docs — no behaviour change.

- DB: table todo_lists -> projects, todo_items -> cards, column
  todo_items.list_id -> cards.project_id, indexes renamed. Migrations 003/004
  rewritten in place (destructive; recreate the volume with `down -v`).
- API: /api/lists -> /api/projects, nested /items -> /cards, reorder body
  item_ids -> card_ids, JSON keys list/lists/item/items -> project/projects/
  card/cards, item_count -> card_count, list_id -> project_id, and the
  matching error messages.
- PHP: TodoList/TodoItem Repository + Controller -> Project/Card; shared SQL
  aliases l/i -> p/c.
- Frontend: stores lists.ts/items.ts -> projects.ts/cards.ts (useProjectsStore
  / useCardsStore, MAX_PROJECTS), ListView -> ProjectView, TodoItemRow ->
  CardRow, route /lists/:id -> /projects/:id (name "project"), types TodoList/
  TodoItem -> Project/Card, and all UI copy. CSS .lists*/.list-head* ->
  .projects*/.project-head*, .item* -> .card-row* (kept the generic .card
  panel class), .items -> .cards.
- Product name in the header, PWA manifest, index.html title and package
  descriptions -> "Project Manager" / "Projects".

Backend suite: 37 passing.

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

web/src/App.vue

@@ -1,18 +1,18 @@
 <script setup lang="ts">
 import { RouterLink, RouterView, useRouter } from 'vue-router'
 import { useAuthStore } from './stores/auth'
-import { useItemsStore } from './stores/items'
-import { useListsStore } from './stores/lists'
+import { useCardsStore } from './stores/cards'
+import { useProjectsStore } from './stores/projects'
 
 const auth = useAuthStore()
-const lists = useListsStore()
-const items = useItemsStore()
+const projects = useProjectsStore()
+const cards = useCardsStore()
 const router = useRouter()
 
 async function onLogout() {
   auth.logout()
-  lists.reset()
-  items.reset()
+  projects.reset()
+  cards.reset()
   await router.push({ name: 'login' })
 }
 </script>
@@ -20,7 +20,7 @@ async function onLogout() {
 <template>
   <div class="app">
     <header class="app__bar">
-      <span class="app__brand">Todo List</span>
+      <span class="app__brand">Projects</span>
 
       <div v-if="auth.isAuthenticated" class="app__account">
         <RouterLink v-if="!auth.emailVerified" to="/profile" class="badge badge--warn">