Add Nebot plugin with Ollama chat integration

Introduces the Nebot plugin, providing a floating chat panel that communicates with a local or remote Ollama server and persists chat sessions. Adds dependencies for markdown rendering and code highlighting (dompurify, highlight.js, marked). Removes the sample-hello plugin. Updates site-history.json with recent browsing history.

package-lock.json

@@ -8,6 +8,11 @@
       "name": "nebula",
       "version": "1.0.0",
       "license": "ISC",
+      "dependencies": {
+        "dompurify": "^3.1.6",
+        "highlight.js": "^11.9.0",
+        "marked": "^12.0.2"
+      },
       "devDependencies": {
         "electron": "^37.3.1",
         "electron-builder": "^23.0.0",
@@ -335,6 +340,13 @@
         "@types/node": "*"
       }
     },
+    "node_modules/@types/trusted-types": {
+      "version": "2.0.7",
+      "resolved": "https://registry.npmjs.org/@types/trusted-types/-/trusted-types-2.0.7.tgz",
+      "integrity": "sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==",
+      "license": "MIT",
+      "optional": true
+    },
     "node_modules/@types/verror": {
       "version": "1.10.11",
       "resolved": "https://registry.npmjs.org/@types/verror/-/verror-1.10.11.tgz",
@@ -1338,6 +1350,15 @@
         "node": ">=8"
       }
     },
+    "node_modules/dompurify": {
+      "version": "3.2.6",
+      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.2.6.tgz",
+      "integrity": "sha512-/2GogDQlohXPZe6D6NOgQvXLPSYBqIWMnZ8zzOhn09REE4eyAzb+Hed3jhoM9OkuaJ8P6ZGTTVWQKAi8ieIzfQ==",
+      "license": "(MPL-2.0 OR Apache-2.0)",
+      "optionalDependencies": {
+        "@types/trusted-types": "^2.0.7"
+      }
+    },
     "node_modules/dotenv": {
       "version": "9.0.2",
       "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-9.0.2.tgz",
@@ -2126,6 +2147,15 @@
         "node": ">= 0.4"
       }
     },
+    "node_modules/highlight.js": {
+      "version": "11.11.1",
+      "resolved": "https://registry.npmjs.org/highlight.js/-/highlight.js-11.11.1.tgz",
+      "integrity": "sha512-Xwwo44whKBVCYoliBQwaPvtd/2tYFkRQtXDWj1nackaV2JPXx3L0+Jvd8/qCJ2p+ML0/XVkJ2q+Mr+UVdpJK5w==",
+      "license": "BSD-3-Clause",
+      "engines": {
+        "node": ">=12.0.0"
+      }
+    },
     "node_modules/hosted-git-info": {
       "version": "4.1.0",
       "resolved": "https://registry.npmjs.org/hosted-git-info/-/hosted-git-info-4.1.0.tgz",
@@ -2428,6 +2458,18 @@
         "node": ">=10"
       }
     },
+    "node_modules/marked": {
+      "version": "12.0.2",
+      "resolved": "https://registry.npmjs.org/marked/-/marked-12.0.2.tgz",
+      "integrity": "sha512-qXUm7e/YKFoqFPYPa3Ukg9xlI5cyAtGmyEIzMfW//m6kXwCy2Ps9DYf5ioijFKQ8qyuscrHoY04iJGctu2Kg0Q==",
+      "license": "MIT",
+      "bin": {
+        "marked": "bin/marked.js"
+      },
+      "engines": {
+        "node": ">= 18"
+      }
+    },
     "node_modules/matcher": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/matcher/-/matcher-3.0.0.tgz",