refactor: per-type resources + simplified classification model

Resources renamed from artifactapi_remote to per-type:
- artifactapi_remote_generic
- artifactapi_remote_docker (with ban_tags)
- artifactapi_remote_helm
- artifactapi_remote_pypi
- artifactapi_remote_npm
- artifactapi_remote_rpm
- artifactapi_remote_alpine
- artifactapi_remote_puppet
- artifactapi_remote_terraform (with releases_remote)
- artifactapi_remote_goproxy

Classification simplified:
- patterns: paths to proxy (empty = all, acts as allowlist)
- blocklist: paths to deny (checked first)
- mutable_patterns: override provider auto-classification
- immutable_patterns: override provider auto-classification
- Provider handles mutability automatically per package type

internal/provider/helpers.go

@@ -0,0 +1,28 @@
+package provider
+
+import (
+	"context"
+
+	"github.com/hashicorp/terraform-plugin-framework/types"
+)
+
+func listToStrings(ctx context.Context, l types.List) []string {
+	if l.IsNull() || l.IsUnknown() {
+		return nil
+	}
+	var result []string
+	l.ElementsAs(ctx, &result, false)
+	return result
+}
+
+func stringsToList(ctx context.Context, ss []string) types.List {
+	if len(ss) == 0 {
+		return types.ListNull(types.StringType)
+	}
+	elems := make([]types.String, len(ss))
+	for i, s := range ss {
+		elems[i] = types.StringValue(s)
+	}
+	list, _ := types.ListValueFrom(ctx, types.StringType, elems)
+	return list
+}