feat(httpclient)!: promote to v1.0.0 — retry-on-429 with Retry-After, DoJSONRequest, bump deps

Extend retry loop to handle HTTP 429 Too Many Requests: when the server includes a
Retry-After header, that duration is used as the retry delay; otherwise falls back to
the configured BackOffDelay. Add DoJSONRequest[Req, Resp] free function that serialises
the request body as JSON, sets Content-Type, and delegates response decoding to DoJSON.
Bump logz and xerrors from v0.9.0 to v1.0.0. API committed as stable.

helpers.go

@@ -1,6 +1,7 @@
 package httpclient
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"io"
@@ -36,6 +37,21 @@ func DoJSON[T any](ctx context.Context, client Client, req *http.Request) (*T, e
 	return &data, nil
 }
 
+// DoJSONRequest serialises body as JSON, POST/PUT/PATCHes it to rawURL, and
+// decodes the response into Resp. For requests without a body, use DoJSON instead.
+func DoJSONRequest[Req, Resp any](ctx context.Context, client Client, method, rawURL string, body Req) (*Resp, error) {
+	data, err := json.Marshal(body)
+	if err != nil {
+		return nil, xerrors.New(xerrors.ErrInternal, "failed to encode request body").WithError(err)
+	}
+	req, err := http.NewRequestWithContext(ctx, method, rawURL, bytes.NewReader(data))
+	if err != nil {
+		return nil, xerrors.New(xerrors.ErrInternal, "failed to create request").WithError(err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+	return DoJSON[Resp](ctx, client, req)
+}
+
 // MapStatusToError maps an HTTP status code to the matching xerrors type.
 func MapStatusToError(code int, msg string) error {
 	switch code {