feat: add math operator wrappers and align TA-Lib binding types

Add Go wrappers for additional TA-Lib math operators:
Div, Max, MaxIndex, Min, MinIndex, MinMax, MinMaxIndex, Mult, Sub, and Sum.

Refactor the TA-Lib function signatures to use int32 consistently,
including taResult and Hilbert Transform bindings, so the Go layer
matches the native library more closely.

Fix HT_TRENDMODE to return []int32 and update related comments and
naming for better API consistency.

loader.go

@@ -33,6 +33,16 @@ func Load() (uintptr, error) {
 	purego.RegisterLibFunc(&ht_sine, ptr, "TA_HT_SINE")
 	purego.RegisterLibFunc(&ht_trendmode, ptr, "TA_HT_TRENDMODE")
 	purego.RegisterLibFunc(&add, ptr, "TA_ADD")
+	purego.RegisterLibFunc(&div, ptr, "TA_DIV")
+	purego.RegisterLibFunc(&max, ptr, "TA_MAX")
+	purego.RegisterLibFunc(&maxIndex, ptr, "TA_MAXINDEX")
+	purego.RegisterLibFunc(&min, ptr, "TA_MIN")
+	purego.RegisterLibFunc(&minIndex, ptr, "TA_MININDEX")
+	purego.RegisterLibFunc(&minMax, ptr, "TA_MINMAX")
+	purego.RegisterLibFunc(&minMaxIndex, ptr, "TA_MINMAXINDEX")
+	purego.RegisterLibFunc(&mult, ptr, "TA_MULT")
+	purego.RegisterLibFunc(&sub, ptr, "TA_SUB")
+	purego.RegisterLibFunc(&sum, ptr, "TA_SUM")
 
 	return ptr, nil
 }