Refactor to Vue 3 + FastAPI + SQLite architecture

- Backend: FastAPI + SQLite (WAL mode), 22 tables, ~40 API endpoints
- Frontend: Vue 3 + Vite + Pinia + Vue Router, 8 views, 3 stores
- Database: migrate from JSON file to SQLite with proper schema
- Dockerfile: multi-stage build (node + python)
- Deploy: K8s manifests (namespace, deployment, service, ingress, pvc, backup)
- CI/CD: Gitea Actions (test, deploy, PR preview at pr-$id.planner.oci.euphon.net)
- Tests: 20 Cypress E2E test files, 196 test cases, ~85% coverage
- Doc: test-coverage.md with full feature coverage report

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/cypress/e2e/music-flow.cy.js

@@ -0,0 +1,61 @@
+describe('Music (音乐打卡)', () => {
+  beforeEach(() => {
+    cy.visit('/music', {
+      onBeforeLoad(win) {
+        win.localStorage.setItem('sp_login_expires', String(Date.now() + 86400000))
+      }
+    })
+    cy.get('header').should('be.visible')
+  })
+
+  it('shows music page with today date', () => {
+    cy.get('.section-header').should('contain', '今日练习')
+    cy.get('.date-label').should('not.be.empty')
+  })
+
+  it('shows practice items section', () => {
+    cy.contains('练习项目').should('be.visible')
+  })
+
+  it('adds a music item to pool', () => {
+    cy.get('.add-row input').type('尤克里里')
+    cy.get('.add-row .btn-accent').click()
+    cy.get('.pool-item').should('contain', '尤克里里')
+  })
+
+  it('adds item to monthly plan', () => {
+    cy.get('.add-row input').type('钢琴')
+    cy.get('.add-row .btn-accent').click()
+    cy.get('.pool-item').contains('钢琴').click()
+    cy.get('.checkin-item').should('contain', '钢琴')
+  })
+
+  it('checks in a music practice', () => {
+    cy.get('.add-row input').type('吉他')
+    cy.get('.add-row .btn-accent').click()
+    cy.get('.pool-item').contains('吉他').click()
+    cy.get('.checkin-item').contains('吉他').click()
+    cy.get('.checkin-item').contains('吉他').should('have.class', 'checked')
+  })
+
+  it('unchecks a music practice', () => {
+    cy.get('.add-row input').type('架子鼓')
+    cy.get('.add-row .btn-accent').click()
+    cy.get('.pool-item').contains('架子鼓').click()
+    cy.get('.checkin-item').contains('架子鼓').click()
+    cy.get('.checkin-item').contains('架子鼓').should('have.class', 'checked')
+    cy.get('.checkin-item').contains('架子鼓').click()
+    cy.get('.checkin-item').contains('架子鼓').should('not.have.class', 'checked')
+  })
+
+  it('deletes a music item', () => {
+    cy.get('.add-row input').type('待删除乐器')
+    cy.get('.add-row .btn-accent').click()
+    cy.get('.pool-item').contains('待删除乐器').parent().find('.remove-btn').click()
+    cy.get('.pool-item').should('not.contain', '待删除乐器')
+  })
+
+  it('empty state shows hint', () => {
+    cy.get('.music-layout').should('be.visible')
+  })
+})