已知数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}\)满足:\(S_{n}=t(S_{n}-a_{n}+1)(t\)为常数,且\(t\neq 0\),\(t\neq 1)\).
\((1)\)求\(\{a_{n}\}\)的通项公式;
\((2)\)设\(b_{n}=a_{n}^{2}+S_{n}a_{n}\),若数列\(\{b_{n}\}\)为等比数列,求\(t\)的值;
\((3)\)在满足条件\((2)\)的情形下,设\(c_{n}=4a_{n}+1\),数列\(\{c_{n}\}\)的前\(n\)项和为\(T_{n}\),若不等式\( \dfrac {12k}{4+n-T_{n}}\geqslant 2n-7\)对任意的\(n∈N^{*}\)恒成立,求实数\(k\)的取值范围.