feat(coding-agent): add project trust gating

packages/coding-agent/src/core/slash-commands.ts

@@ -30,6 +30,7 @@ export const BUILTIN_SLASH_COMMANDS: ReadonlyArray<BuiltinSlashCommand> = [
 	{ name: "fork", description: "Create a new fork from a previous user message" },
 	{ name: "clone", description: "Duplicate the current session at the current position" },
 	{ name: "tree", description: "Navigate session tree (switch branches)" },
+	{ name: "trust", description: "Save project trust decision for future sessions" },
 	{ name: "login", description: "Configure provider authentication" },
 	{ name: "logout", description: "Remove provider authentication" },
 	{ name: "new", description: "Start a new session" },