fix(ui): self-host Google Fonts to eliminate third-party dependency

Replace the runtime @import of Google Fonts with self-hosted woff2 files
served from public/fonts/. This removes the external network dependency
and prevents leaking client metadata (IP, user-agent, referrer) to
third-party origins, improving CSP compatibility and privacy.

- Bundle Poppins (weights 100-600) and Roboto Mono (400) as woff2
- Add @font-face declarations pointing to local files
- Remove the Google Fonts @import
- Include OFL license file for bundled fonts

Relates to #6292

Signed-off-by: Yomi <yomi@users.noreply.github.com>

Author: yomete

ui/packages/app/web/public/fonts/LICENSE

@@ -0,0 +1,12 @@
+The font files in this directory are licensed under the SIL Open Font License, Version 1.1.
+
+Poppins
+  Copyright 2020 The Poppins Project Authors (https://github.com/itfoundry/Poppins)
+  License: https://fonts.google.com/specimen/Poppins/license
+
+Roboto Mono
+  Copyright 2015 The Roboto Mono Project Authors (https://github.com/googlefonts/RobotoMono)
+  License: https://fonts.google.com/specimen/Roboto+Mono/license
+
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+https://openfontlicense.org

ui/packages/app/web/public/fonts/poppins-100.woff2

@@ -1,4 +1,58 @@
-@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@100;200;300;400;500;600&family=Roboto+Mono&display=swap');
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 100;
+  font-display: swap;
+  src: url('/fonts/poppins-100.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 200;
+  font-display: swap;
+  src: url('/fonts/poppins-200.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 300;
+  font-display: swap;
+  src: url('/fonts/poppins-300.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 400;
+  font-display: swap;
+  src: url('/fonts/poppins-400.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 500;
+  font-display: swap;
+  src: url('/fonts/poppins-500.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Poppins';
+  font-style: normal;
+  font-weight: 600;
+  font-display: swap;
+  src: url('/fonts/poppins-600.woff2') format('woff2');
+}
+
+@font-face {
+  font-family: 'Roboto Mono';
+  font-style: normal;
+  font-weight: 400;
+  font-display: swap;
+  src: url('/fonts/roboto-mono-400.woff2') format('woff2');
+}
 
 .profile-search-bar .queryExpressionInput {
   box-shadow: none;