milestone 32: task-shaped configuration, file mode as a rendering, config status api

src/tests.zig

@@ -119,6 +119,7 @@ comptime {
     _ = @import("web/handlers/upstreams.zig");
     _ = @import("web/handlers/pause.zig");
     _ = @import("web/handlers/settings.zig");
+    _ = @import("web/handlers/config.zig");
     _ = @import("web/handlers/auth.zig");
     _ = @import("web/static.zig");
     _ = @import("web/openapi.zig");