chore(deploy): drop deploy.sh and manifest.yml now that workflow runs

First end-to-end run of the deploy workflow succeeded (gitea run #289),
so the operator-run rolling-deploy script and its YAML manifest are no
longer the source of truth — fleet topology lives in
.gitea/workflows/deploy.yml and per-host config in script/infra-setup.sh.

Per-host neuron config comments updated to point at the new sync path.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

asset/neuron/quadbrat.toml

@@ -4,7 +4,7 @@
 # (bf16, ~4 GB), leaving ~7 GB for KV cache so long contexts on a small
 # model still have plenty of room.
 #
-# Synced by script/deploy.sh from asset/neuron/<short-host>.toml.
+# Synced to /etc/neuron/neuron.toml by script/infra-setup.sh.
 
 port = 13131