feat(physarum): add slime mold network demo

Add a Physarum route with a GPU trail map and a CPU fallback.
Tick the Physarum item in ROADMAP.md.

src/app/constants/RouterConstants.ts

@@ -60,6 +60,11 @@
     LINK: '/algorithms/boids',
   };
 
+  static readonly PHYSARUM = {
+    PATH: 'algorithms/physarum',
+    LINK: '/algorithms/physarum',
+  };
+
   static readonly FOUR_COLOR = {
     PATH: 'algorithms/four_color',
     LINK: '/algorithms/four_color',

src/app/constants/UrlConstants.ts

@@ -23,6 +23,8 @@
   static readonly XPBD_WIKI = 'https://www.emergentmind.com/topics/extended-position-based-dynamics-xpbd'
   static readonly BOIDS_WIKI = 'https://de.wikipedia.org/wiki/Boids'
   static readonly PARTICLE_LIFE_WIKI = 'https://particle-life.com'
+  static readonly PHYSARUM_WIKI = 'https://en.wikipedia.org/wiki/Physarum_polycephalum'
+  static readonly PHYSARUM_PAPER = 'https://doi.org/10.1162/artl.2010.16.2.16202'
   static readonly GPU_COMPUTING_WIKI = 'https://en.wikipedia.org/wiki/General-purpose_computing_on_graphics_processing_units'
   static readonly DATA_STRUCTURE_WIKI = 'https://de.wikipedia.org/wiki/Datenstruktur'
   static readonly FOUR_COLOR_THEOREM = 'https://de.wikipedia.org/wiki/Vier-Farben-Satz'