refactor(v2): drop @chat-adapter/shared dep — duck-type NetworkError

The only use was channel-registry.ts checking `err instanceof NetworkError`
to retry transient setup failures. Switched to a duck-type predicate
(`err.name === 'NetworkError'`) so the dep is no longer needed at trunk
level. Channel skills bring it in transitively when they install their
Chat SDK adapter package.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pnpm-lock.yaml

@@ -8,9 +8,6 @@ importers:
 
   .:
     dependencies:
-      '@chat-adapter/shared':
-        specifier: ^4.24.0
-        version: 4.26.0
       '@onecli-sh/sdk':
         specifier: ^0.3.1
         version: 0.3.1
@@ -66,9 +63,6 @@ importers:
 
 packages:
 
-  '@chat-adapter/shared@4.26.0':
-    resolution: {integrity: sha512-YD0MGktFXrArUqTBsyPfL5vkdD1WBS58PAWO0oVrMQAMmPxpAXfWGjBtZCkf3y8R8Svb0uVuVXiMZSForaEnMQ==}
-
   '@emnapi/core@1.9.2':
     resolution: {integrity: sha512-UC+ZhH3XtczQYfOlu3lNEkdW/p4dsJ1r/bP7H8+rhao3TTTMO1ATq/4DdIi23XuGoFY+Cz0JmCbdVl0hz9jZcA==}
 
@@ -1516,12 +1510,6 @@ packages:
 
 snapshots:
 
-  '@chat-adapter/shared@4.26.0':
-    dependencies:
-      chat: 4.26.0
-    transitivePeerDependencies:
-      - supports-color
-
   '@emnapi/core@1.9.2':
     dependencies:
       '@emnapi/wasi-threads': 1.2.1