refactor(paths): collapse harness home resolution into one resolver

Delete @deepseek-ai/dsh-home and make dsh-paths the sole owner of the
single-root harness home ($DSH_HOME || ~/.dsh). Migrate tool-bash,
skill-local, and agent-spine-demo off dsh-home, and fold telemetry's
divergent globalConfigDir onto the shared resolver, dropping its second
XDG/APPDATA policy and the deepseek-harness namespace so the anonymous
id lives under the harness home. Add dshHomeDisplay() for symbolic
user-facing paths, replacing workspace-context's bespoke check.

packages/sdk/telemetry/tsconfig.json

@@ -8,6 +8,7 @@
     "src"
   ],
   "references": [
-    { "path": "../../util/brand" }
+    { "path": "../../util/brand" },
+    { "path": "../../util/paths" }
   ]
 }