chore(brand): swap header logo to a real svg + ship favicons for portal-admin

Two related brand-asset cleanups bundled per request:

portal-shell — header logo:
- Replace `apf-small.png` (a 7.6 KB raster wrapped through sharp from
  the original PNG-in-SVG file) with `apf-logo.svg`, an actual
  vector 1024×1024 export (2.1 KB). Sharper at any density, smaller
  payload, no rasterisation artefacts when the header zooms.
- `header.html` swaps the `<img src=…>` accordingly.
- The wide-format `apf-portal.svg` stays in place for future
  surfaces (login splash, etc.).

portal-admin — favicons + PWA manifest:
- Mirror portal-shell's PR #84 setup. Copy the six favicon image
  assets (favicon.ico, favicon.svg, favicon-96x96.png,
  apple-touch-icon.png, web-app-manifest-{192,512}.png) into
  `apps/portal-admin/public/favicons/`. Single visual identity
  across the two apps.
- Customise `site.webmanifest`: `name: "APF Portal Admin"`,
  `short_name: "Admin"`. PWA install banners and home-screen
  icons read the right app name when admin is installed
  standalone. Icon entries + theme-color + display stay identical
  to portal-shell.
- Wire `<link>` tags in `apps/portal-admin/src/index.html` mirroring
  portal-shell's, plus `<meta name="theme-color">`.
- Remove the now-obsolete top-level `apps/portal-admin/public/favicon.ico`
  (replaced by the entry under `favicons/`, referenced via
  `<link rel="shortcut icon">`).

Verified: `nx run-many -t lint test build --projects=portal-shell,
portal-admin` green; both `dist/.../browser/{en,fr}/favicons/` ship
the seven expected files; admin manifest contains "APF Portal Admin";
admin `index.html` has the right `<link>` block.

apps/portal-shell/public/logos/apf-logo.svg

@@ -0,0 +1 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?><!-- Generator: Gravitdesign.com --><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" style="isolation:isolate" viewBox="0 0 1024 1024" width="1024pt" height="1024pt"><defs><clipPath id="_clipPath_B4TZ570FigxU4c50hle9QrZwbv6YvFBZ"><rect width="1024" height="1024"/></clipPath></defs><g clip-path="url(#_clipPath_B4TZ570FigxU4c50hle9QrZwbv6YvFBZ)"><path d=" M 302.7 566.118 C 355.817 515.422 427.036 483.173 501.691 480.62 C 626.026 477.14 721.654 557.185 738.018 669.829 C 734.571 656.604 628.618 409.16 302.701 566.118 L 302.7 566.118 Z " fill="rgb(247,169,25)"/><g><path d=" M 732.849 505.91 C 675.421 450.11 499.114 228.071 514.048 161.831 C 530.416 89.558 636.371 30.51 735.43 0 C 719.64 2.552 706.724 5.104 694.661 8.585 C 586.122 37.355 472.984 99.302 454.893 175.868 C 439.96 241.297 498.247 315.31 562.572 378.65 C 584.25 400.069 569.598 402.126 540.415 406.219 C 515.859 409.664 481.014 414.554 448.867 433.637 C 527.084 402.036 655.737 470.669 711.434 500.382 C 735.478 513.208 745.922 518.782 732.849 505.91 L 732.849 505.91 Z " fill="rgb(18,84,108)"/><path d=" M 711.885 266.354 C 737.15 226.331 785.688 206.494 821.289 222.039 C 856.897 237.816 865.799 283.06 841.394 323.894 C 816.989 363.917 768.451 384.102 732.85 368.325 C 697.242 352.78 687.774 307.538 711.885 266.354 Z " fill="rgb(18,84,108)"/><path d=" M 307.282 582.591 C 617.41 441.409 727.668 675.86 732.836 700.109 C 735.416 720.173 735.416 742.1 731.969 763.679 C 711.878 907.414 578.07 1024 433.052 1024 C 288.045 1024 187.249 907.414 207.353 763.679 C 217.694 693.146 255.022 629.459 307.282 582.591 L 307.282 582.591 Z  M 450.565 937.11 C 546.769 937.11 636.357 859.614 649.278 763.679 C 663.344 668.089 595.583 590.364 499.101 590.364 C 467.005 590.364 435.702 598.966 407.73 613.965 C 388.702 624.169 371.215 637.334 356.069 652.766 C 326.553 682.839 305.925 721.522 300.1 763.679 C 286.323 859.614 354.084 937.11 450.566 937.11 L 450.565 937.11 Z " fill-rule="evenodd" fill="rgb(18,84,108)"/></g></g></svg>

apps/portal-shell/src/app/components/header/header.html

@@ -8,7 +8,7 @@
       [class.justify-center]="collapsed()"
     >
       <img
-        src="logos/apf-small.png"
+        src="logos/apf-logo.svg"
         alt=""
         aria-hidden="true"
         width="36"