Where does 'contentment' fit in walking the path of Dhamma? 'Contentment' means being at ease with what you have and not desiring more. But, of course, if I am content with my present situation I will not strive towards Nirvana, and if I am not content and desire for more I invite suffering. Is 'contentment' described in any of the Buddhist scriptures? How to make use of it in the path towards
Nirvana?
The sutta SN 16.1 is about contentment.
From SN 16.1:

At Savatthī. “Bhikkhus, this Kassapa is content with any kind of robe,
and he speaks in praise of contentment with any kind of robe, and he
does not engage in a wrong search, in what is improper, for the sake
of a robe. If he does not get a robe he is not agitated, and if he
gets one he uses it without being tied to it, uninfatuated with it,
not blindly absorbed in it, seeing the danger in it, understanding the
escape.
“Bhikkhus, this Kassapa is content with any kind of almsfood … with
any kind of lodging … with any kind of medicinal requisites … and if
he gets them he uses them without being tied to them, uninfatuated
with them, not blindly absorbed in them, seeing the danger in them,
understanding the escape.
“Therefore, bhikkhus, you should train yourselves thus: ‘We will be
content with any kind of robe, and we will speak in praise of
contentment with any kind of robe, and we will not engage in a wrong
search, in what is improper, for the sake of a robe. If we do not get
a robe we will not be agitated, and if we get one we will use it
without being tied to it, uninfatuated with it, not blindly absorbed
in it, seeing the danger in it, understanding the escape.
“‘We will be content with any kind of almsfood … with any kind of
lodging … with any kind of medicinal requisites … and if we get them
we will use them without being tied to them, uninfatuated with them,
not blindly absorbed in them, seeing the danger in them, understanding
the escape.’ Thus should you train yourselves.
“Bhikkhus, I will exhort you by the example of Kassapa or one who is
similar to Kassapa. Being exhorted, you should practise accordingly.”

Also AN 6.114:

“Mendicants, there are these three things. What three? Lack of
contentment, lack of situational awareness, and having many wishes.
These are the three things. To give up these three things you should
develop three things. What three? You should develop contentment to
give up lack of contentment, situational awareness to give up lack of
situational awareness, and having few wishes to give up having many
wishes. These are the three things you should develop to give up those
three things.”