Add BlocklistSource interface and implementations for fetching blocklist data

- Introduced `BlocklistSource` interface with `Get` method to retrieve IPv4/IPv6 blocklists.
- Added `blocklistSource` and `blocklistSourceZip` structures to support standard and ZIP-configured data sources.

internal/daemon/blocklist/sources/source.go

@@ -0,0 +1,46 @@
+package sources
+
+import (
+	"git.kor-elf.net/kor-elf-shield/blocklist"
+	"git.kor-elf.net/kor-elf-shield/blocklist/parser"
+)
+
+type BlocklistSource interface {
+	Get() (ipV4 parser.IPs, ipV6 parser.IPs, err error)
+}
+
+type blocklistSource struct {
+	url    string
+	parser parser.Parser
+	config blocklist.Config
+}
+
+func NewBlocklistSource(url string, parser parser.Parser, config blocklist.Config) BlocklistSource {
+	return &blocklistSource{
+		url:    url,
+		parser: parser,
+		config: config,
+	}
+}
+
+func (b *blocklistSource) Get() (ipV4 parser.IPs, ipV6 parser.IPs, err error) {
+	return blocklist.GetSeparatedIPs(b.url, b.parser, b.config)
+}
+
+type blocklistSourceZip struct {
+	url    string
+	parser parser.Parser
+	config blocklist.ConfigZip
+}
+
+func NewBlocklistSourceZip(url string, parser parser.Parser, config blocklist.ConfigZip) BlocklistSource {
+	return &blocklistSourceZip{
+		url:    url,
+		parser: parser,
+		config: config,
+	}
+}
+
+func (b *blocklistSourceZip) Get() (ipV4 parser.IPs, ipV6 parser.IPs, err error) {
+	return blocklist.GetZipSeparatedIPs(b.url, b.parser, b.config)
+}