std.sync.atomic: extended atomic helper functions (#8866)

- deprecates `std.Thread.spinLoopHint` and moves it to `std.atomic.spinLoopHint`
- added an Atomic(T) generic wrapper type which replaces atomic.Bool and atomic.Int
- in Atomic(T), selectively expose member functions depending on T and include bitwise atomic methods when T is an Integer
- added fence() and compilerFence() to std.atomic

lib/std/json.zig

@@ -2111,7 +2111,10 @@ test "parse into struct with duplicate field" {
     const ballast = try testing.allocator.alloc(u64, 1);
     defer testing.allocator.free(ballast);
 
-    const options_first = ParseOptions{ .allocator = testing.allocator, .duplicate_field_behavior = .UseFirst };
+    const options_first = ParseOptions{
+        .allocator = testing.allocator,
+        .duplicate_field_behavior = .UseFirst,
+    };
 
     const options_last = ParseOptions{
         .allocator = testing.allocator,