Merge the concurrent selector adaptation; ui-model stays the model owner

The remote side re-merged master (i18n workflow round) and restored the
pre-architecture ModelSelector package with the Session-side state
machine. Reconciliation keeps that merge's master content and reasserts
this branch's model architecture: business state lives in ui-model's
shared per-session directory (ctx.models), not on Session/
ConversationSnapshot; the input.model seat entry and the /model popup
stay the two same-source entries; the history modelTarget piggyback stays
removed. The ui-model-selector package, its roster row, and its allowlist
entry go; the smoke-real roster names ui-model.

apps/cli/cordis.yml

@@ -283,6 +283,7 @@
 - id: ui-conversation
   name: '@deepseek-ai/dsh-client-ui-conversation'
 
+
 - id: ui-workspace
   name: '@deepseek-ai/dsh-client-ui-workspace'
 
@@ -300,7 +301,7 @@
 - id: ui-subagent
   name: '@deepseek-ai/dsh-client-ui-subagent'
 
-# Model selection: the /model popupSelect over session.models / selectModel.
+# Model selection: the /model popupSelect + composer seat over session.models.
 - id: ui-model
   name: '@deepseek-ai/dsh-client-ui-model'