fix: use direct HTTPS URL for libsignal dependency

The root cause was simple: Yarn converts git+https:// to SSH.

Solution: Change package.json to use direct HTTPS URL
- Before: "git+https://github.com/whiskeysockets/libsignal-node"
- After: "https://github.com/whiskeysockets/libsignal-node.git"

This eliminates SSH conversion completely and works with all package managers.

Also simplified workflow by removing unnecessary workarounds:
- Removed temporary package.json patching step
- Removed retry logic
- Restored simple 'yarn install --immutable'

Clean, permanent solution. 🎯

package.json

@@ -45,7 +45,7 @@
     "@hapi/boom": "^9.1.3",
     "async-mutex": "^0.5.0",
     "fflate": "^0.8.2",
-    "libsignal": "git+https://github.com/whiskeysockets/libsignal-node",
+    "libsignal": "https://github.com/whiskeysockets/libsignal-node.git",
     "lru-cache": "^11.1.0",
     "music-metadata": "^11.7.0",
     "p-queue": "^9.0.0",