[Prim][NewIR] change decomposition to return new vars in New IR

[cyber-pioneer]

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PR changes

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Description

Pcard-66975
In new ir program, once some operator is decomposed, its vars will be replaced by new ones. If some vars will be used later, corresponding vars will be returned for later usage.

Example:

def fn(x):
    var1 = op1(x)
    var2 = op2(var1)
    var3 = op3(var2)
    return var1, var3

# src_vars = [var1, var3]
src_vars = fn(x) 

# dst_vars = [var1', var3']
dst_vars = decompose(program_fn)

# src_vars is released and replaced by dst_vars.
res = fn_n(*src_vars) # bad
res = fn_n(*dst_vars) # ok

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