influxdb: serve org and bucket from its settings (issue 696)

A settings layer will stop replacing what a provider serves (ADR 0348
clause 11). influxdb on ace relies on that today: its layer sets org and
bucket over the served literals, and grafana writes the bucket into its
data source. Serving ${setting:org} and ${setting:bucket}, with today's
literals as defaults, keeps every consumer's binding the same before and
after the controller change. Declaring settings means runtime-config names
the keys it takes; it keeps every key its client reads.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

modules/influxdb/module.json

@@ -26,12 +26,24 @@
       "why": "queries, writes and the web UI, over http; consumers granted influxdb-api sign in with the mesh's credential, and a name is a route grant"
     }
   ],
+  "settings": {
+    "org": {
+      "kind": "preference",
+      "default": "mesh",
+      "why": "the organisation influxdb-api names to its consumers; mesh is the one influxdb makes at its first start (server.env), and a machine whose server was set up with another sets its own (novox/hq issue 696, ADR 0348 clause 11)"
+    },
+    "bucket": {
+      "kind": "preference",
+      "default": "default",
+      "why": "the bucket influxdb-api names to its consumers; default is the one influxdb makes at its first start (server.env), and a machine whose server was set up with another sets its own (novox/hq issue 696, ADR 0348 clause 11)"
+    }
+  },
   "serves": {
     "influxdb-api": {
       "scheme": "http",
       "port": 8086,
-      "org": "mesh",
-      "bucket": "default"
+      "org": "${setting:org}",
+      "bucket": "${setting:bucket}"
     }
   },
   "receives": {
@@ -124,7 +136,13 @@
       "path": "${dir:mesh-state}/config.json",
       "mode": "0600",
       "content": "{}\n",
-      "merge": "json"
+      "merge": "json",
+      "takes-settings": [
+        "bucket",
+        "org",
+        "url"
+      ],
+      "trusted": true
     }
   ],
   "requires": [