fix(channels): truncate Telegram and Discord upstream error bodies to 200 bytes (#22075)

internal/channels/discord.go

@@ -624,7 +624,7 @@ func (c *discordChannel) requestJSON(ctx context.Context, method, path string, b
 		if resp.StatusCode == http.StatusTooManyRequests {
 			return newDiscordRateLimitError(resp.Header, respBody)
 		}
-		return fmt.Errorf("discord api status: %d, response: %s", resp.StatusCode, string(respBody))
+		return fmt.Errorf("discord api status: %d, response: %.200s", resp.StatusCode, respBody)
 	}
 	if out != nil && len(bytes.TrimSpace(respBody)) > 0 {
 		return json.Unmarshal(respBody, out)
@@ -649,7 +649,7 @@ func newDiscordRateLimitError(header http.Header, body []byte) *discordRateLimit
 	return &discordRateLimitError{
 		RetryAfter: retryAfter,
 		Global:     payload.Global,
-		Response:   strings.TrimSpace(string(body)),
+		Response:   fmt.Sprintf("%.200s", strings.TrimSpace(string(body))),
 	}
 }
 

internal/channels/telegram.go

@@ -380,7 +380,7 @@ func (c *telegramChannel) callAPI(ctx context.Context, method string, params map
 		return err
 	}
 	if resp.StatusCode >= http.StatusBadRequest {
-		return fmt.Errorf("Telegram API %s returned status %d: %s", method, resp.StatusCode, string(body))
+		return fmt.Errorf("Telegram API %s returned status %d: %.200s", method, resp.StatusCode, body)
 	}
 
 	var response telegramAPIResponse
@@ -388,7 +388,7 @@ func (c *telegramChannel) callAPI(ctx context.Context, method string, params map
 		return fmt.Errorf("Telegram API %s returned invalid JSON: %w", method, err)
 	}
 	if !response.OK {
-		return fmt.Errorf("Telegram API %s failed: %s", method, response.Description)
+		return fmt.Errorf("Telegram API %s failed: %.200s", method, response.Description)
 	}
 	if out != nil && len(response.Result) > 0 {
 		if err := json.Unmarshal(response.Result, out); err != nil {