feat: add image fetch with proxy support and registry proxy config

Backend:
- Add image fetch handler using go-containerregistry
- Support HTTP/HTTPS and SOCKS5 proxy protocols
- Pull images from remote registries (Docker Hub, etc.)
- Store fetched images as blobs and manifests
- Add timeout handling (60s for descriptor fetch)
- Add detailed logging for pull progress
- Add /api/v1/registry/image/fetch endpoint

Frontend:
- Add registry proxy configuration field
- Add "获取镜像" button and dialog
- Add proxy checkbox and input in fetch dialog
- Add LinearProgress feedback during fetch
- Add multi-stage Snackbar notifications
- Auto-refresh image list after successful fetch
- Fix download filename regex (remove trailing quote)
- Adjust button colors for better UI consistency

Dependencies:
- Add github.com/google/go-containerregistry for OCI operations
- Add golang.org/x/net/proxy for SOCKS5 support

🤖 Generated with [Qoder](https://qoder.com)

go.mod

@@ -6,14 +6,19 @@ require (
 	github.com/glebarez/sqlite v1.11.0
 	github.com/gofiber/fiber/v3 v3.0.0-beta.2
 	github.com/gofrs/uuid v4.4.0+incompatible
+	github.com/google/go-containerregistry v0.20.6
 	github.com/jedib0t/go-pretty/v6 v6.7.1
 	github.com/spf13/cobra v1.10.1
-	golang.org/x/crypto v0.41.0
+	golang.org/x/crypto v0.43.0
 	gorm.io/gorm v1.31.1
 )
 
 require (
 	github.com/andybalholm/brotli v1.2.0 // indirect
+	github.com/containerd/stargz-snapshotter/estargz v0.16.3 // indirect
+	github.com/docker/cli v28.2.2+incompatible // indirect
+	github.com/docker/distribution v2.8.3+incompatible // indirect
+	github.com/docker/docker-credential-helpers v0.9.3 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/glebarez/go-sqlite v1.21.2 // indirect
 	github.com/gofiber/utils/v2 v2.0.0-rc.1 // indirect
@@ -25,13 +30,21 @@ require (
 	github.com/mattn/go-colorable v0.1.14 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-runewidth v0.0.16 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
+	github.com/opencontainers/image-spec v1.1.1 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/spf13/pflag v1.0.9 // indirect
 	github.com/stretchr/testify v1.11.1 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/valyala/fasthttp v1.65.0 // indirect
-	golang.org/x/sys v0.36.0 // indirect
+	github.com/vbatts/tar-split v0.12.1 // indirect
+	golang.org/x/net v0.46.0 // indirect
+	golang.org/x/sync v0.17.0 // indirect
+	golang.org/x/sys v0.37.0 // indirect
 	golang.org/x/text v0.30.0 // indirect
 	modernc.org/libc v1.22.5 // indirect
 	modernc.org/mathutil v1.5.0 // indirect