feat: support map and slice types in OBI attributes

Extends OBI header parsing to recognize and deserialize JSON-like arrays and objects. Introduces safe conversion utilities in `obiutils` to cast generic interface values into typed maps, and exposes them via new `BioSequence` methods. Header values are now marshaled, quote-normalized, and formatted for map and slice types.

pkg/obiseq/biosequence_test.go

@@ -103,7 +103,7 @@ func TestNewBioSequence(t *testing.T) {
 // Return type: None.
 func TestNewBioSequenceWithQualities(t *testing.T) {
 	id := "123"
-	sequence := []byte("ATGC")
+	sequence := []byte("atgc")
 	definition := "DNA sequence"
 	qualities := []byte("1234")