cli: handle "-e" as the command to execute

src/cli/args.zig

@@ -64,6 +64,11 @@ pub fn parse(comptime T: type, alloc: Allocator, dst: *T, iter: anytype) !void {
     };
 
     while (iter.next()) |arg| {
+        // Do manual parsing if we have a hook for it.
+        if (@hasDecl(T, "parseManuallyHook")) {
+            if (!try dst.parseManuallyHook(arena_alloc, arg, iter)) return;
+        }
+
         if (mem.startsWith(u8, arg, "--")) {
             var key: []const u8 = arg[2..];
             const value: ?[]const u8 = value: {