feat: rename to gitea-mcp-extended and add package publishing workflows

Rename the fork from gitea-mcp to gitea-mcp-extended to reflect the
significantly expanded tool coverage (299 vs upstream's 93 tools).

- Rename Go module path and all import references
- Rename binary to gitea-mcp-extended in Makefile, Dockerfile, .gitignore
- Point .goreleaser.yaml gitea_urls to git.lethalbits.com
- Replace release-tag workflow with goreleaser + Generic Package Registry publishing
- Replace release-nightly workflow with cross-platform build + nightly package publishing
- Update CLAUDE.md project description and tool count

cmd/cmd.go

@@ -7,9 +7,9 @@ import (
 	"os"
 	"text/tabwriter"
 
-	"git.lethalbits.com/lethalbits/gitea-mcp/operation"
-	flagPkg "git.lethalbits.com/lethalbits/gitea-mcp/pkg/flag"
-	"git.lethalbits.com/lethalbits/gitea-mcp/pkg/log"
+	"git.lethalbits.com/lethalbits/gitea-mcp-extended/operation"
+	flagPkg "git.lethalbits.com/lethalbits/gitea-mcp-extended/pkg/flag"
+	"git.lethalbits.com/lethalbits/gitea-mcp-extended/pkg/log"
 )
 
 var (
@@ -39,7 +39,7 @@ func init() {
 
 	flag.Usage = func() {
 		w := tabwriter.NewWriter(os.Stderr, 0, 0, 3, ' ', 0)
-		fmt.Fprintln(os.Stderr, "Usage: gitea-mcp [options]")
+		fmt.Fprintln(os.Stderr, "Usage: gitea-mcp-extended [options]")
 		fmt.Fprintln(os.Stderr)
 		fmt.Fprintln(os.Stderr, "Options:")
 		fmt.Fprintf(w, "  -t, -transport <type>\tTransport type: stdio or http (default: stdio)\n")