chore: deploy to Cloudflare Pages and update branding

- Add Cloudflare Pages deployment for landing page (snapotter.com) and
  docs (docs.snapotter.com)
- Create deploy-landing.yml and update deploy-docs.yml workflows
- Update CI to ignore apps/landing/** paths
- Fix logo transparency (remove white background) across all apps
- Recreate social-preview.png with SnapOtter branding
- Update all docs URLs from GitHub Pages to docs.snapotter.com
- Update VitePress config: light theme default, fix llms.txt paths
- Add .vitepress/cache/ and .env.* to gitignore

tests/e2e-docker/utility-tools.spec.ts

@@ -405,7 +405,7 @@ test.describe("QR Generate", () => {
     const res = await request.post("/api/v1/tools/qr-generate", {
       headers: { Authorization: `Bearer ${token}` },
       data: {
-        text: "https://ashim.app",
+        text: "https://snapotter.app",
         size: 512,
       },
     });
@@ -434,7 +434,7 @@ test.describe("QR Generate", () => {
     const res = await request.post("/api/v1/tools/qr-generate", {
       headers: { Authorization: `Bearer ${token}` },
       data: {
-        text: "https://github.com/ashim-hq/ashim",
+        text: "https://github.com/snapotter/snapotter",
         size: 300,
         errorCorrection: "H",
       },