Add memory-viewer from silicondawn

- Web UI for browsing and editing OpenClaw memory files
- Cloned from https://github.com/silicondawn/memory-viewer
- Built and running on port 8901
- Features: file tree, markdown rendering, search, live reload
- Full access to MEMORY.md, daily notes, skills, automations

memory-viewer/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "files": [],
+  "references": [
+    { "path": "./tsconfig.app.json" },
+    { "path": "./tsconfig.node.json" }
+  ]
+}