feat(bootstrap): add shared session bootstrap and machine-alias resolver

policies/MACHINE-ALIASES.yaml

@@ -0,0 +1,14 @@
+version: 1
+machines:
+  - hostname: mac-5
+    aliases: mac5,control,openclaw-control
+    default_agent_suffix: mac5
+  - hostname: lingyuzeng-X99-TI-D4-PLUS
+    aliases: rtx2080ti,gpu-gateway,group
+    default_agent_suffix: rtx2080ti
+  - hostname: mac-6
+    aliases: mac6,executor,node-exec
+    default_agent_suffix: mac6
+  - hostname: mac-7
+    aliases: mac7,browser,node-browser
+    default_agent_suffix: mac7