Add mesh-hand-acts, holder of the seat mesh-hand-acts, so the hand-act log has a home the controller's lease does not hold (issue 1953)

Acts are kept 400 days under the runtime-proven caller and said as act-recorded; a warrant is read from the router's own record and recorded once per ask; hand-acts answers over both logs. The act layout is a copy of mesh-sdk's until L5-S2 lands.

modules/mesh-hand-acts/module.json

@@ -0,0 +1,69 @@
+{
+  "module": "mesh-hand-acts",
+  "version": "1",
+  "runs-as": "mesh-hand-acts",
+  "claims": [
+    {
+      "name": "mesh-hand-acts",
+      "scope": "mesh",
+      "serves": [
+        "hand-act",
+        "hand-acts",
+        "warranted"
+      ]
+    }
+  ],
+  "emits": [
+    "act-recorded"
+  ],
+  "reads": [
+    "mesh-controller.hand-acts",
+    "messenger.asks"
+  ],
+  "state": [
+    {
+      "name": "acts",
+      "ttl-seconds": 34560000
+    },
+    {
+      "name": "warrants",
+      "ttl-seconds": 34560000
+    }
+  ],
+  "own-secrets": {
+    "broker": "${dir:state}/broker"
+  },
+  "secrets-owner": "mesh-hand-acts",
+  "resources": [
+    {
+      "id": "account",
+      "type": "user",
+      "name": "mesh-hand-acts",
+      "shell": "/usr/bin/nologin",
+      "home": "/var/lib/mesh-hand-acts"
+    },
+    {
+      "id": "state",
+      "type": "directory",
+      "mode": "0700",
+      "owner": "mesh-hand-acts",
+      "place": ".",
+      "unknown": "program"
+    }
+  ],
+  "build": {
+    "artifacts": [
+      {
+        "name": "tools",
+        "kind": "bundle",
+        "language": "go",
+        "system": "arch",
+        "from": "cmd/mesh-hand-acts",
+        "binary": "mesh-hand-acts",
+        "loads": [
+          "mesh-hand-acts"
+        ]
+      }
+    ]
+  }
+}