chore(cogs): publish cog-person-count + cog-pose-estimation 0.3.0 to crates.io

- cog-person-count: no path deps, clean publish.
- cog-pose-estimation: added explicit version="0.3.1" to the
  wifi-densepose-train path dep (crates.io rejects path-only deps).
- cog-ha-matter: keeps publish=false; the published
  wifi-densepose-sensing-server@0.3.0 does not expose the `mqtt` feature
  this cog requires. Note added inline; republish sensing-server with the
  feature exposed before dropping the flag.

Co-Authored-By: claude-flow <ruv@ruv.net>

v2/crates/cog-pose-estimation/Cargo.toml

@@ -6,7 +6,6 @@ authors.workspace = true
 license.workspace = true
 repository.workspace = true
 description = "Cognitum Cog: 17-keypoint pose estimation from WiFi CSI. See ADR-100 (packaging) + ADR-101 (this Cog)."
-publish = false
 
 [[bin]]
 name = "cog-pose-estimation"
@@ -36,7 +35,7 @@ candle-nn = { version = "0.9", default-features = false }
 safetensors = "0.4"
 # wifi-densepose-train re-exports the model types we need; depend by path
 # inside the workspace.
-wifi-densepose-train = { path = "../wifi-densepose-train", default-features = false }
+wifi-densepose-train = { version = "0.3.1", path = "../wifi-densepose-train", default-features = false }
 
 [dev-dependencies]
 tempfile = "3"