feat: improve session sharing and Kimi transcript support

- normalize Kimi thinking parts and omit empty placeholders
- add standalone session-sharing and UI demo artifacts
- add regression coverage and refresh the Kimi index marker
- bump the Electron app and CLI packages to v0.2.1
- ignore generated app build assets

app/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "obelisk",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "obelisk",
-      "version": "0.2.0",
+      "version": "0.2.1",
       "dependencies": {
         "better-sqlite3": "^11.0.0",
         "chokidar": "^4.0.3"