chore: the SSH aliases and CI's runner label keep the servers' names

The servers' names are no secret, so the settings that carry them stay
as they were, and nothing on a server or a laptop needs changing: CI
runs on `sahaquiel` again, the release uploads to `ramiel-fdroid`, and
deploys by hand go through `sahaquiel-deploy`. Prose still names a
server by the domain it serves, which says what a reader needs.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

deploy/runner/config.yml

@@ -20,8 +20,8 @@ runner:
   # code.halkyon.app's server, a one-core one.
   fetch_interval: 10s
   report_interval: 1s
-  # `runs-on: instance` in a workflow means: here, on the instance's server, on the host.
-  labels: ["instance:host"]
+  # `runs-on: sahaquiel` in a workflow means: here, on the instance's server, on the host.
+  labels: ["sahaquiel:host"]
 
 cache:
   # No cache server (it would listen on a port of its own); the SDKs and package