ax(mining): replace banned fmt.Errorf with package error constructors in miner.go

Remove `fmt` import from miner.go; replace all fmt.Errorf calls with
ErrInstallFailed, ErrInternal, and ErrMinerNotFound using .WithCause/.WithDetails.

Co-Authored-By: Charon <charon@lethean.io>

pkg/mining/miner.go

@@ -5,7 +5,6 @@ import (
 	"archive/zip"
 	"bytes"
 	"compress/gzip"
-	"fmt"
 	"io"
 	"net/http"
 	"os"
@@ -260,7 +259,7 @@ func (b *BaseMiner) InstallFromURL(url string) error {
 
 	if resp.StatusCode != http.StatusOK {
 		_, _ = io.Copy(io.Discard, resp.Body) // Drain body to allow connection reuse (error ignored intentionally)
-		return fmt.Errorf("failed to download release: unexpected status code %d", resp.StatusCode)
+		return ErrInstallFailed(b.ExecutableName).WithDetails("unexpected status code " + strconv.Itoa(resp.StatusCode))
 	}
 
 	if _, err := io.Copy(tmpfile, resp.Body); err != nil {
@@ -280,7 +279,7 @@ func (b *BaseMiner) InstallFromURL(url string) error {
 		err = b.untar(tmpfile.Name(), baseInstallPath)
 	}
 	if err != nil {
-		return fmt.Errorf("failed to extract miner: %w", err)
+		return ErrInstallFailed(b.ExecutableName).WithCause(err).WithDetails("failed to extract archive")
 	}
 
 	return nil
@@ -376,14 +375,14 @@ func (b *BaseMiner) findMinerBinary() (string, error) {
 	if err == nil {
 		absPath, err := filepath.Abs(path)
 		if err != nil {
-			return "", fmt.Errorf("failed to get absolute path for '%s': %w", path, err)
+			return "", ErrInternal("failed to get absolute path for '" + path + "'").WithCause(err)
 		}
 		logging.Debug("found miner binary in system PATH", logging.Fields{"path": absPath})
 		return absPath, nil
 	}
 
 	// If not found, return a detailed error
-	return "", fmt.Errorf("miner executable '%s' not found. Searched in: %s and system PATH", executableName, strings.Join(searchedPaths, ", "))
+	return "", ErrMinerNotFound(executableName).WithDetails("searched in: " + strings.Join(searchedPaths, ", ") + " and system PATH")
 }
 
 // details, err := miner.CheckInstallation()
@@ -556,11 +555,11 @@ func (b *BaseMiner) unzip(src, dest string) error {
 	for _, f := range r.File {
 		fpath := filepath.Join(dest, f.Name)
 		if !strings.HasPrefix(fpath, filepath.Clean(dest)+string(os.PathSeparator)) {
-			return fmt.Errorf("%s: illegal file path", fpath)
+			return ErrInternal("illegal file path in archive").WithDetails(fpath)
 		}
 		if f.FileInfo().IsDir() {
 			if err := os.MkdirAll(fpath, os.ModePerm); err != nil {
-				return fmt.Errorf("failed to create directory %s: %w", fpath, err)
+				return ErrInternal("failed to create directory").WithCause(err).WithDetails(fpath)
 			}
 			continue
 		}
@@ -614,7 +613,7 @@ func (b *BaseMiner) untar(src, dest string) error {
 
 		target := filepath.Join(dest, header.Name)
 		if !strings.HasPrefix(target, filepath.Clean(dest)+string(os.PathSeparator)) {
-			return fmt.Errorf("%s: illegal file path in archive", header.Name)
+			return ErrInternal("illegal file path in archive").WithDetails(header.Name)
 		}
 
 		switch header.Typeflag {