4.
平面直角坐标系\(xOy\)中,曲线\(C:{{(x-1)}^{2}}+{{y}^{2}}=1 .\)直线\(l\)经过点\(P(m,0)\),且倾斜角为\(\dfrac{\pi }{6} .\)以\(O\)为极点,以\(x\)轴正半轴为极轴,建立极坐标系.
\((1)\)写出曲线\(C\)的极坐标方程与直线\(l\)的参数方程;
\((2)\)若直线\(l\)与曲线\(C\)相交于\(A,B\)两点,且\(\left| PA \right|\cdot \left| PB \right|=1\),求实数\(m\)的值.