refactor: brand the command lifecycle pairing id as CommandId

commandId crosses three boundaries (session log, wire admission response,
client flow pairing), so per the branded-id rule it becomes
Branded<'CommandId'>, declared in a new pure @deepseek-ai/dsh-commands/brand
outlet (the dsh-llm/brand shape: type + constructor, no Context merges, so
wire and client programs can name it without loading the host plugin). The
event payloads, CommandExecution, and the executor mint carry the brand; the
wire schema gains commandIdSchema as the domain's single brand-cast point
(the approvals precedent); CommandNode and the fixture's fabrication cast
follow type-only.

packages/ui/commands/package.json

@@ -15,12 +15,17 @@
       "types": "./lib/types/invariant.d.ts",
       "default": "./lib/invariant.js"
     },
+    "./brand": {
+      "types": "./lib/types/brand.d.ts",
+      "default": "./lib/types/brand.js"
+    },
     "./src/*": "./src/*",
     "./package.json": "./package.json"
   },
   "files": [
     "lib/index.js",
     "lib/invariant.js",
+    "lib/types/**/*.js",
     "lib/types/**/*.d.ts",
     "lib/types/**/*.d.ts.map",
     "src"
@@ -28,6 +33,7 @@
   "license": "BSD-3-Clause",
   "peerDependencies": {
     "@deepseek-ai/dsh-agent": "^0.0.1",
+    "@deepseek-ai/dsh-brand": "^0.0.1",
     "@deepseek-ai/dsh-invariants": "^0.0.1",
     "@deepseek-ai/dsh-scope": "^0.0.1",
     "@deepseek-ai/dsh-session": "^0.0.1",
@@ -35,6 +41,7 @@
   },
   "devDependencies": {
     "@deepseek-ai/dsh-agent": "workspace:^",
+    "@deepseek-ai/dsh-brand": "workspace:^",
     "@deepseek-ai/dsh-invariants": "workspace:^",
     "@deepseek-ai/dsh-scope": "workspace:^",
     "@deepseek-ai/dsh-session": "workspace:^",