refactor: split web frontend + gateway out to uniweb app (bump 0.13.0)

The SPA (web/) and the web gateway (cmd/webgw) move to a dedicated app
projects/message_bus/apps/uniweb (its own Gitea sub-repo). unibus is now
strictly the bus plane: membership/keys, the client library and demo peers.
uniweb consumes unibus as a Go module via replace => ../unibus.

No capability lost; same SPA and gateway, in their own service folder.
go build/vet/test green after extraction.

web/node_modules/.bin/vite

@@ -0,0 +1,22 @@
+#!/bin/sh
+basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
+
+case `uname` in
+    *CYGWIN*|*MINGW*|*MSYS*)
+        if command -v cygpath > /dev/null 2>&1; then
+            basedir=`cygpath -w "$basedir"`
+        fi
+    ;;
+esac
+
+if [ -z "$NODE_PATH" ]; then
+  export NODE_PATH="/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/vite@6.4.3_sugarss@5.0.1_postcss@8.5.15_/node_modules/vite/node_modules:/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/vite@6.4.3_sugarss@5.0.1_postcss@8.5.15_/node_modules:/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/node_modules"
+else
+  export NODE_PATH="/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/vite@6.4.3_sugarss@5.0.1_postcss@8.5.15_/node_modules/vite/node_modules:/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/vite@6.4.3_sugarss@5.0.1_postcss@8.5.15_/node_modules:/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/.pnpm/node_modules:$NODE_PATH"
+fi
+if [ -x "$basedir/node" ]; then
+  exec "$basedir/node"  "$basedir/../vite/bin/vite.js" "$@"
+else
+  exec node  "$basedir/../vite/bin/vite.js" "$@"
+fi
+# cmd-shim-target=/home/enmanuel/fn_registry/projects/message_bus/apps/unibus/web/node_modules/vite/bin/vite.js