Add registry provider as sync source for Docker Registry V2 API

AGENTS.md

@@ -57,7 +57,7 @@ Recognized types:
 - `custom_files`
 
 Notes:
-- `registry` is used as a target for image push operations.
+- `registry` can be used as a **sync source** (enumerating repositories/tags and pulling manifests+blobs from a registry) and/or as a **push target** for `airgap registry push`.
 - `custom_files` is accepted as config type but not wired as a sync provider yet.
 
 ## Code Change Expectations

CHANGELOG.md

@@ -2,6 +2,16 @@
 
 All notable changes to this project are documented in this file.
 
+## 0.4.0 - 2026-02-26
+
+### Added
+
+- **Registry as sync source**: the `registry` provider type can now act as a sync source, enumerating repository tags via the Docker Registry V2 API and downloading manifests/blobs locally. Configure with `repositories`, `tags` (glob filters), and `output_dir` fields.
+- Registry provider UI form updated with sync source sections (repositories, tag filters, output directory) alongside existing push target fields.
+- Sync history table on provider detail page showing the last 10 sync runs with duration, status, and transfer stats.
+- Dashboard empty state with "Get Started" prompt when no providers are configured.
+- Dynamic version display in sidebar (uses build-time `version` variable instead of hardcoded value).
+
 ## 0.3.5 - 2026-02-24
 
 ### Changed

cmd/airgap/root.go

@@ -15,6 +15,7 @@ import (
 	"github.com/BadgerOps/airgap/internal/provider/containerimages"
 	"github.com/BadgerOps/airgap/internal/provider/epel"
 	"github.com/BadgerOps/airgap/internal/provider/ocp"
+	registryprovider "github.com/BadgerOps/airgap/internal/provider/registry"
 	"github.com/BadgerOps/airgap/internal/store"
 	"github.com/spf13/cobra"
 )
@@ -159,7 +160,9 @@ func createProvider(typeName, dataDir string, log *slog.Logger) (provider.Provid
 		return ocp.NewRHCOSProvider(dataDir, log), nil
 	case "container_images":
 		return containerimages.NewProvider(dataDir, log), nil
-	case "registry", "custom_files":
+	case "registry":
+		return registryprovider.NewProvider(dataDir, log), nil
+	case "custom_files":
 		return nil, fmt.Errorf("provider type %q is not yet implemented", typeName)
 	default:
 		return nil, fmt.Errorf("unknown provider type: %q", typeName)

cmd/airgap/serve.go

@@ -59,6 +59,7 @@ func serveRun(cmd *cobra.Command, args []string) error {
 
 	// Create the HTTP server
 	srv := server.NewServer(globalEngine, globalRegistry, globalStore, globalCfg, logger)
+	srv.SetVersion(version)
 
 	// Channel to listen for errors from server
 	errChan := make(chan error, 1)

internal/config/config.go

@@ -99,17 +99,24 @@ type ContainerImagesProviderConfig struct {
 	OutputDir      string `yaml:"output_dir"`
 }
 
-// RegistryProviderConfig is the typed config for mirror-registry
+// RegistryProviderConfig is the typed config for mirror-registry.
+// When Repositories is non-empty the provider acts as a sync source,
+// enumerating tags via the Docker Registry V2 API and downloading
+// manifests/blobs locally. When Repositories is empty it is a push-only
+// target used by `airgap registry push`.
 type RegistryProviderConfig struct {
-	Enabled              bool   `yaml:"enabled"`
-	MirrorRegistryBinary string `yaml:"mirror_registry_binary"`
-	QuayRoot             string `yaml:"quay_root"`
-	Endpoint             string `yaml:"endpoint"`
-	RepositoryPrefix     string `yaml:"repository_prefix"`
-	Username             string `yaml:"username"`
-	Password             string `yaml:"password"`
-	InsecureSkipTLS      bool   `yaml:"insecure_skip_tls"`
-	SkopeoBinary         string `yaml:"skopeo_binary"`
+	Enabled              bool     `yaml:"enabled"`
+	MirrorRegistryBinary string   `yaml:"mirror_registry_binary"`
+	QuayRoot             string   `yaml:"quay_root"`
+	Endpoint             string   `yaml:"endpoint"`
+	RepositoryPrefix     string   `yaml:"repository_prefix"`
+	Username             string   `yaml:"username"`
+	Password             string   `yaml:"password"`
+	InsecureSkipTLS      bool     `yaml:"insecure_skip_tls"`
+	SkopeoBinary         string   `yaml:"skopeo_binary"`
+	Repositories         []string `yaml:"repositories"`
+	Tags                 []string `yaml:"tags"`
+	OutputDir            string   `yaml:"output_dir"`
 }
 
 // CustomFilesProviderConfig is the typed config for custom file sources