docs(content-guide): voice rule — 'the infrastructure I manage', never a home lab or host count

docs/content-guide.md

@@ -12,6 +12,16 @@ Two hard rules flow from that:
 1. **Attach your identity to every post** — photo, bio, links. Anonymous content kills E-E-A-T and defeats the whole purpose.
 2. **Pitch to learners, not experts.** Most search traffic comes from people learning. Write down, not up.
 
+### Voice: "the infrastructure I manage", never "my home lab"
+
+Frame the estate as work, not as a hobby: **"the infrastructure I manage" / "我管理的机器"**.
+
+- ❌ "my home machines", "my four hosts", "my home lab", "四台全中", a host count in the title/description/OG.
+- ✅ Name what the systems are (DSM NAS, unRaid, a CyberPanel VM, a VPS) and let measured evidence carry the
+  scale — container counts, site counts, byte-identical output, minutes-to-patch.
+
+A reader should see someone who runs other people's production, not someone tinkering in a basement.
+
 ---
 
 ## 2. Categories (stable — don't invent new ones casually)