docs: make project documentation self-contained

package-lock.json

@@ -8,7 +8,8 @@
       "name": "wealth-ledger-docs",
       "version": "1.0.0",
       "devDependencies": {
-        "markdownlint-cli2": "0.23.2"
+        "markdownlint-cli2": "0.23.2",
+        "markdownlint-rule-relative-links": "5.1.2"
       },
       "engines": {
         "node": "22.x"
@@ -601,6 +602,20 @@
         "markdownlint-cli2": ">=0.0.4"
       }
     },
+    "node_modules/markdownlint-rule-relative-links": {
+      "version": "5.1.2",
+      "resolved": "https://registry.npmjs.org/markdownlint-rule-relative-links/-/markdownlint-rule-relative-links-5.1.2.tgz",
+      "integrity": "sha512-mskM3EOV7SdAPEfhaLzdtaZ/25S/i6ef0sX6+O2LqqD7JvHgaY1OLVgMb3ZfybD90DFLRhzry3LieF+W/uS3gA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "markdown-it": "14.3.0",
+        "mime": "4.1.0"
+      },
+      "engines": {
+        "node": ">=22.0.0"
+      }
+    },
     "node_modules/mdurl": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/mdurl/-/mdurl-2.1.0.tgz",
@@ -1168,6 +1183,22 @@
         "node": ">=8.6"
       }
     },
+    "node_modules/mime": {
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/mime/-/mime-4.1.0.tgz",
+      "integrity": "sha512-X5ju04+cAzsojXKes0B/S4tcYtFAJ6tTMuSPBEn9CPGlrWr8Fiw7qYeLT0XyH80HSoAoqWCaz+MWKh22P7G1cw==",
+      "dev": true,
+      "funding": [
+        "https://github.com/sponsors/broofa"
+      ],
+      "license": "MIT",
+      "bin": {
+        "mime": "bin/cli.js"
+      },
+      "engines": {
+        "node": ">=16"
+      }
+    },
     "node_modules/ms": {
       "version": "2.1.3",
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",