refactor(frontend): restructure project layout and update API schema

Relocate frontend source code from `next-app/` to `frontend/` to align with the new project structure. This includes removing the old Next.js boilerplate files and establishing a cleaner workspace.

Additionally, updates the OpenAPI specification to include support for the `immich` widget type and its corresponding configuration schema.

- Move frontend files to `frontend/`
- Delete obsolete `next-app/` directory and its configuration
- Add `immich` widget type to `openapi.yaml`
- Update `FrontendPlan.md` with dashboard refactor and UX direction

frontend/test-results/.last-run.json

@@ -0,0 +1,7 @@
+{
+  "status": "failed",
+  "failedTests": [
+    "4219922fea2e2bd3c691-2c97ef6de38543745b6a",
+    "4219922fea2e2bd3c691-afdb8990cae2360e1f04"
+  ]
+}

frontend/test-results/smoke-smoke-page-loads-with-header-chromium/error-context.md

@@ -0,0 +1,80 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: smoke.spec.ts >> smoke: page loads with header
+- Location: e2e/smoke.spec.ts:3:5
+
+# Error details
+
+```
+Error: expect(locator).toBeVisible() failed
+
+Locator: locator('header')
+Expected: visible
+Timeout: 5000ms
+Error: element(s) not found
+
+Call log:
+  - Expect "toBeVisible" with timeout 5000ms
+  - waiting for locator('header')
+
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - alert [ref=e2]
+  - generic [ref=e7] [cursor=pointer]:
+    - button "Open Next.js Dev Tools" [ref=e8]:
+      - img [ref=e9]
+    - generic [ref=e12]:
+      - button "Open issues overlay" [ref=e13]:
+        - generic [ref=e14]:
+          - generic [ref=e15]: "0"
+          - generic [ref=e16]: "1"
+        - generic [ref=e17]: Issue
+      - button "Collapse issues badge" [ref=e18]:
+        - img [ref=e19]
+  - generic [ref=e21]:
+    - img [ref=e22]
+    - paragraph [ref=e24]: Failed to load dashboard
+    - paragraph [ref=e25]: Failed to fetch
+```
+
+# Test source
+
+```ts
+  1  | import { test, expect } from "@playwright/test";
+  2  | 
+  3  | test("smoke: page loads with header", async ({ page }) => {
+  4  |   await page.goto("http://localhost:3000");
+> 5  |   await expect(page.locator("header")).toBeVisible();
+     |                                        ^ Error: expect(locator).toBeVisible() failed
+  6  |   await expect(page.getByText("Dash")).toBeVisible();
+  7  | });
+  8  | 
+  9  | test("smoke: theme toggle works", async ({ page }) => {
+  10 |   await page.goto("http://localhost:3000");
+  11 |   const toggle = page.getByLabel("Toggle theme");
+  12 |   await toggle.click();
+  13 |   await page.getByText("CasaOS").click();
+  14 |   const theme = await page.evaluate(() => document.documentElement.getAttribute("data-theme"));
+  15 |   expect(theme).toBe("casaos");
+  16 | });
+  17 | 
+  18 | test("smoke: empty state shows add button", async ({ page }) => {
+  19 |   await page.goto("http://localhost:3000");
+  20 |   // If no services exist, the empty state should be visible
+  21 |   const emptyState = page.getByText("No apps yet");
+  22 |   if (await emptyState.isVisible()) {
+  23 |     await expect(page.getByRole("button", { name: /add app/i })).toBeVisible();
+  24 |   }
+  25 | });
+  26 | 
+```

frontend/test-results/smoke-smoke-theme-toggle-works-chromium/error-context.md

@@ -0,0 +1,77 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: smoke.spec.ts >> smoke: theme toggle works
+- Location: e2e/smoke.spec.ts:9:5
+
+# Error details
+
+```
+Test timeout of 30000ms exceeded.
+```
+
+```
+Error: locator.click: Test timeout of 30000ms exceeded.
+Call log:
+  - waiting for getByLabel('Toggle theme')
+
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - alert [ref=e2]
+  - generic [ref=e7] [cursor=pointer]:
+    - button "Open Next.js Dev Tools" [ref=e8]:
+      - img [ref=e9]
+    - generic [ref=e12]:
+      - button "Open issues overlay" [ref=e13]:
+        - generic [ref=e14]:
+          - generic [ref=e15]: "0"
+          - generic [ref=e16]: "1"
+        - generic [ref=e17]: Issue
+      - button "Collapse issues badge" [ref=e18]:
+        - img [ref=e19]
+  - generic [ref=e21]:
+    - img [ref=e22]
+    - paragraph [ref=e24]: Failed to load dashboard
+    - paragraph [ref=e25]: Failed to fetch
+```
+
+# Test source
+
+```ts
+  1  | import { test, expect } from "@playwright/test";
+  2  | 
+  3  | test("smoke: page loads with header", async ({ page }) => {
+  4  |   await page.goto("http://localhost:3000");
+  5  |   await expect(page.locator("header")).toBeVisible();
+  6  |   await expect(page.getByText("Dash")).toBeVisible();
+  7  | });
+  8  | 
+  9  | test("smoke: theme toggle works", async ({ page }) => {
+  10 |   await page.goto("http://localhost:3000");
+  11 |   const toggle = page.getByLabel("Toggle theme");
+> 12 |   await toggle.click();
+     |                ^ Error: locator.click: Test timeout of 30000ms exceeded.
+  13 |   await page.getByText("CasaOS").click();
+  14 |   const theme = await page.evaluate(() => document.documentElement.getAttribute("data-theme"));
+  15 |   expect(theme).toBe("casaos");
+  16 | });
+  17 | 
+  18 | test("smoke: empty state shows add button", async ({ page }) => {
+  19 |   await page.goto("http://localhost:3000");
+  20 |   // If no services exist, the empty state should be visible
+  21 |   const emptyState = page.getByText("No apps yet");
+  22 |   if (await emptyState.isVisible()) {
+  23 |     await expect(page.getByRole("button", { name: /add app/i })).toBeVisible();
+  24 |   }
+  25 | });
+  26 | 
+```