The Alabama mom allegedly butchered by her teen son had fought with him about her Facebook posts — where she once griped about his “attitude” — in the hours leading up to the gruesome attack that also left her husband fighting for his life, a neighbor exclusively revealed to The Post. Samantha Baker, 37 — who was found dead from multiple stab wounds outside an Augustine Drive home in the private Belforest complex late Sunday — had tried to put her enraged 17-year-old son Brandon in his place earlier that day, according to the family’s next-door neighbor, Shawn Scurry.  Surveillance…