Implement M1.5 visual design foundation: tokens, IBM Plex, theme toggle, chart themes

package-lock.json

@@ -8,6 +8,8 @@
       "name": "astrolabe",
       "version": "0.1.0",
       "dependencies": {
+        "@fontsource/ibm-plex-mono": "^5.2.7",
+        "@fontsource/ibm-plex-sans": "^5.2.8",
         "monaco-editor": "^0.54.0",
         "react": "^19.2.7",
         "react-dom": "^19.2.7",
@@ -2061,6 +2063,24 @@
         "node": ">=18"
       }
     },
+    "node_modules/@fontsource/ibm-plex-mono": {
+      "version": "5.2.7",
+      "resolved": "https://registry.npmjs.org/@fontsource/ibm-plex-mono/-/ibm-plex-mono-5.2.7.tgz",
+      "integrity": "sha512-MKAb8qV+CaiMQn2B0dIi1OV3565NYzp3WN5b4oT6LTkk+F0jR6j0ZN+5BKJiIhffDC3rtBULsYZE65+0018z9w==",
+      "license": "OFL-1.1",
+      "funding": {
+        "url": "https://github.com/sponsors/ayuhito"
+      }
+    },
+    "node_modules/@fontsource/ibm-plex-sans": {
+      "version": "5.2.8",
+      "resolved": "https://registry.npmjs.org/@fontsource/ibm-plex-sans/-/ibm-plex-sans-5.2.8.tgz",
+      "integrity": "sha512-eztSXjDhPhcpxNIiGTgMebdLP9qS4rWkysuE1V7c+DjOR0qiezaiDaTwQE7bTnG5HxAY/8M43XKDvs3cYq6ZYQ==",
+      "license": "OFL-1.1",
+      "funding": {
+        "url": "https://github.com/sponsors/ayuhito"
+      }
+    },
     "node_modules/@isaacs/cliui": {
       "version": "9.0.0",
       "resolved": "https://registry.npmjs.org/@isaacs/cliui/-/cliui-9.0.0.tgz",