feat: add chat sharing foundation (#25041)

cli/testdata/coder_server_--help.golden

@@ -36,6 +36,10 @@ OPTIONS:
           creating a token without specifying a duration, such as when
           authenticating the CLI or an IDE plugin.
 
+      --disable-chat-sharing bool, $CODER_DISABLE_CHAT_SHARING
+          Disable chat sharing. Chat ACL checking is disabled and only owners
+          can access their chats.
+
       --disable-owner-workspace-access bool, $CODER_DISABLE_OWNER_WORKSPACE_ACCESS
           Remove the permission for the 'owner' role to have workspace execution
           on all workspaces. This prevents the 'owner' from ssh, apps, and

cli/testdata/server-config.yaml.golden

@@ -530,6 +530,10 @@ disableOwnerWorkspaceAccess: false
 # --disable-owner-workspace-access.
 # (default: <unset>, type: bool)
 disableWorkspaceSharing: false
+# Disable chat sharing. Chat ACL checking is disabled and only owners can access
+# their chats.
+# (default: <unset>, type: bool)
+disableChatSharing: false
 # These options change the behavior of how clients interact with the Coder.
 # Clients include the Coder CLI, Coder Desktop, IDE extensions, and the web UI.
 client: