docs: add README, per-resource examples, unit tests, CI, and pre-commit

- Add README.md with provider docs, resource/data-source reference, and
  development instructions
- Reorganize examples into per-resource-type subdirectories following
  Terraform provider conventions, add missing pypi/npm/puppet examples
- Add unit tests for helpers, HTTP client, model conversions, and
  provider registration
- Add Woodpecker CI pipelines for lint, test, and build
- Add pre-commit config with standard and Go-specific hooks

internal/provider/helpers_test.go

@@ -0,0 +1,105 @@
+package provider
+
+import (
+	"context"
+	"testing"
+
+	"github.com/hashicorp/terraform-plugin-framework/types"
+)
+
+func TestListToStrings_NullList(t *testing.T) {
+	ctx := context.Background()
+	null := types.ListNull(types.StringType)
+	result := listToStrings(ctx, null)
+	if result != nil {
+		t.Fatalf("expected nil for null list, got %v", result)
+	}
+}
+
+func TestListToStrings_UnknownList(t *testing.T) {
+	ctx := context.Background()
+	unknown := types.ListUnknown(types.StringType)
+	result := listToStrings(ctx, unknown)
+	if result != nil {
+		t.Fatalf("expected nil for unknown list, got %v", result)
+	}
+}
+
+func TestListToStrings_EmptyList(t *testing.T) {
+	ctx := context.Background()
+	list, diags := types.ListValueFrom(ctx, types.StringType, []types.String{})
+	if diags.HasError() {
+		t.Fatalf("unexpected diags: %v", diags)
+	}
+	result := listToStrings(ctx, list)
+	if len(result) != 0 {
+		t.Fatalf("expected empty slice, got %v", result)
+	}
+}
+
+func TestListToStrings_WithValues(t *testing.T) {
+	ctx := context.Background()
+	elems := []types.String{
+		types.StringValue("alpha"),
+		types.StringValue("beta"),
+		types.StringValue("gamma"),
+	}
+	list, diags := types.ListValueFrom(ctx, types.StringType, elems)
+	if diags.HasError() {
+		t.Fatalf("unexpected diags: %v", diags)
+	}
+	result := listToStrings(ctx, list)
+	if len(result) != 3 {
+		t.Fatalf("expected 3 elements, got %d", len(result))
+	}
+	expected := []string{"alpha", "beta", "gamma"}
+	for i, v := range result {
+		if v != expected[i] {
+			t.Errorf("index %d: expected %q, got %q", i, expected[i], v)
+		}
+	}
+}
+
+func TestStringsToList_EmptySlice(t *testing.T) {
+	ctx := context.Background()
+	result := stringsToList(ctx, []string{})
+	if !result.IsNull() {
+		t.Fatalf("expected null list for empty slice, got %v", result)
+	}
+}
+
+func TestStringsToList_NilSlice(t *testing.T) {
+	ctx := context.Background()
+	result := stringsToList(ctx, nil)
+	if !result.IsNull() {
+		t.Fatalf("expected null list for nil slice, got %v", result)
+	}
+}
+
+func TestStringsToList_WithValues(t *testing.T) {
+	ctx := context.Background()
+	result := stringsToList(ctx, []string{"one", "two", "three"})
+	if result.IsNull() || result.IsUnknown() {
+		t.Fatalf("expected non-null non-unknown list, got null=%v unknown=%v", result.IsNull(), result.IsUnknown())
+	}
+	// Round-trip: convert back and verify
+	back := listToStrings(ctx, result)
+	if len(back) != 3 {
+		t.Fatalf("expected 3 elements after round-trip, got %d", len(back))
+	}
+	expected := []string{"one", "two", "three"}
+	for i, v := range back {
+		if v != expected[i] {
+			t.Errorf("round-trip index %d: expected %q, got %q", i, expected[i], v)
+		}
+	}
+}
+
+func TestStringsToList_SingleValue(t *testing.T) {
+	ctx := context.Background()
+	result := stringsToList(ctx, []string{"solo"})
+	back := listToStrings(ctx, result)
+	if len(back) != 1 || back[0] != "solo" {
+		t.Fatalf("expected [\"solo\"], got %v", back)
+	}
+}