gpu: add TODOs about documentation

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

gpu/src/Adapter.zig

@@ -95,6 +95,7 @@ pub const Type = enum(u32) {
     unknown,
 };
 
+// TODO: docs
 pub fn typeName(t: Type) []const u8 {
     return switch (t) {
         .discrete_gpu => "Discrete GPU",
@@ -116,6 +117,7 @@ pub const BackendType = enum(u32) {
     opengles,
 };
 
+// TODO: docs
 pub fn backendTypeName(t: BackendType) []const u8 {
     return switch (t) {
         .nul => "Null",

gpu/src/Device.zig

@@ -52,6 +52,7 @@ pub const VTable = struct {
     release: fn (ptr: *anyopaque) void,
 };
 
+// TODO: docs
 pub const Descriptor = struct {
     label: ?[]const u8 = null,
     required_features: ?[]FeatureName = null,

gpu/src/Surface.zig

@@ -29,6 +29,7 @@ pub const DescriptorTag = enum {
     canvas_html_selector,
 };
 
+// TODO: docs
 pub const Descriptor = union(DescriptorTag) {
     metal_layer: struct {
         label: ?[]const u8,

gpu/src/main.zig

@@ -14,7 +14,10 @@
 //!
 //! Note: WebGPU’s coordinate systems match DirectX’s coordinate systems in a graphics pipeline.
 //!
-//! 
+//! # Reference counting
+//!
+//! TODO: docs
+//!
 const std = @import("std");
 pub const Interface = @import("Interface.zig");
 pub const RequestAdapterOptions = Interface.RequestAdapterOptions;