Posthog, scarf and url navigation overhaul (#4318)

Added post hog project - always enabled
Added scarf pixel - Always enabled 
Reworked Url navigation 
Forward and back now works without reloading page

---------

Co-authored-by: Connor Yoh <[email protected]>

frontend/package-lock.json

@@ -32,6 +32,7 @@
         "jszip": "^3.10.1",
         "pdf-lib": "^1.17.1",
         "pdfjs-dist": "^3.11.174",
+        "posthog-js": "^1.261.0",
         "react": "^19.1.0",
         "react-dom": "^19.1.0",
         "react-i18next": "^15.5.2",
@@ -1774,6 +1775,12 @@
         "url": "https://opencollective.com/popperjs"
       }
     },
+    "node_modules/@posthog/core": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/@posthog/core/-/core-1.0.2.tgz",
+      "integrity": "sha512-hWk3rUtJl2crQK0WNmwg13n82hnTwB99BT99/XI5gZSvIlYZ1TPmMZE8H2dhJJ98J/rm9vYJ/UXNzw3RV5HTpQ==",
+      "license": "MIT"
+    },
     "node_modules/@rolldown/pluginutils": {
       "version": "1.0.0-beta.9",
       "resolved": "https://registry.npmjs.org/@rolldown/pluginutils/-/pluginutils-1.0.0-beta.9.tgz",
@@ -3813,6 +3820,17 @@
         "node": ">=18"
       }
     },
+    "node_modules/core-js": {
+      "version": "3.45.1",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-3.45.1.tgz",
+      "integrity": "sha512-L4NPsJlCfZsPeXukyzHFlg/i7IIVwHSItR0wg0FLNqYClJ4MQYTYLbC7EkjKYRLZF2iof2MUgN0EGy7MdQFChg==",
+      "hasInstallScript": true,
+      "license": "MIT",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/core-js"
+      }
+    },
     "node_modules/core-util-is": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.3.tgz",
@@ -4614,6 +4632,12 @@
         "reusify": "^1.0.4"
       }
     },
+    "node_modules/fflate": {
+      "version": "0.4.8",
+      "resolved": "https://registry.npmjs.org/fflate/-/fflate-0.4.8.tgz",
+      "integrity": "sha512-FJqqoDBR00Mdj9ppamLa/Y7vxm+PRmNWA67N846RvsoYVMKB4q3y/de5PA7gUmRMYK/8CMz2GDZQmCRN1wBcWA==",
+      "license": "MIT"
+    },
     "node_modules/file-selector": {
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/file-selector/-/file-selector-2.1.2.tgz",
@@ -7388,6 +7412,47 @@
         "postcss": "^8.2.9"
       }
     },
+    "node_modules/posthog-js": {
+      "version": "1.261.0",
+      "resolved": "https://registry.npmjs.org/posthog-js/-/posthog-js-1.261.0.tgz",
+      "integrity": "sha512-jyiXqyrCU+VlpbNNVRA6OQYAVut0XZMYNELCZH+XvTd981VqbE4jXn4XCBreo7XCL2gdPgDVxUVOuzNvEuKcmw==",
+      "license": "SEE LICENSE IN LICENSE",
+      "dependencies": {
+        "@posthog/core": "1.0.2",
+        "core-js": "^3.38.1",
+        "fflate": "^0.4.8",
+        "preact": "^10.19.3",
+        "web-vitals": "^4.2.4"
+      },
+      "peerDependencies": {
+        "@rrweb/types": "2.0.0-alpha.17",
+        "rrweb-snapshot": "2.0.0-alpha.17"
+      },
+      "peerDependenciesMeta": {
+        "@rrweb/types": {
+          "optional": true
+        },
+        "rrweb-snapshot": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/posthog-js/node_modules/web-vitals": {
+      "version": "4.2.4",
+      "resolved": "https://registry.npmjs.org/web-vitals/-/web-vitals-4.2.4.tgz",
+      "integrity": "sha512-r4DIlprAGwJ7YM11VZp4R884m0Vmgr6EAKe3P+kO0PPj3Unqyvv59rczf6UiGcb9Z8QxZVcqKNwv/g0WNdWwsw==",
+      "license": "Apache-2.0"
+    },
+    "node_modules/preact": {
+      "version": "10.27.1",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-10.27.1.tgz",
+      "integrity": "sha512-V79raXEWch/rbqoNc7nT9E4ep7lu+mI3+sBmfRD4i1M73R3WLYcCtdI0ibxGVf4eQL8ZIz2nFacqEC+rmnOORQ==",
+      "license": "MIT",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/preact"
+      }
+    },
     "node_modules/precinct": {
       "version": "12.2.0",
       "resolved": "https://registry.npmjs.org/precinct/-/precinct-12.2.0.tgz",