refactor: use errors.New for static error strings

integrations/playback/allanime/availability.go

@@ -2,7 +2,7 @@ package allanime
 
 import (
 	"context"
-	"fmt"
+	"errors"
 	"mal/internal/domain"
 	"strconv"
 	"strings"
@@ -48,17 +48,17 @@ func (c *AllAnimeProvider) GetAvailableEpisodes(ctx context.Context, showID stri
 
 	data, ok := result["data"].(map[string]any)
 	if !ok {
-		return AvailableEpisodes{}, fmt.Errorf("invalid response")
+		return AvailableEpisodes{}, errors.New("invalid response")
 	}
 
 	show, ok := data["show"].(map[string]any)
 	if !ok || show == nil {
-		return AvailableEpisodes{}, fmt.Errorf("show not found")
+		return AvailableEpisodes{}, errors.New("show not found")
 	}
 
 	detail, ok := show["availableEpisodesDetail"].(map[string]any)
 	if !ok {
-		return AvailableEpisodes{}, fmt.Errorf("invalid detail")
+		return AvailableEpisodes{}, errors.New("invalid detail")
 	}
 
 	return AvailableEpisodes{

integrations/playback/allanime/crypto.go

@@ -6,6 +6,7 @@ import (
 	"crypto/sha256"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"strings"
 )
@@ -21,7 +22,7 @@ func decryptTobeparsed(encoded string) ([]byte, error) {
 	}
 
 	if len(raw) < 29 {
-		return nil, fmt.Errorf("encrypted payload too short")
+		return nil, errors.New("encrypted payload too short")
 	}
 
 	version := raw[0]
@@ -54,7 +55,7 @@ func decryptTobeparsed(encoded string) ([]byte, error) {
 		}
 	}
 
-	return nil, fmt.Errorf("decryption failed")
+	return nil, errors.New("decryption failed")
 }
 
 func tryDecryptCTR(block cipher.Block, iv []byte, cipherText []byte) []byte {

integrations/playback/allanime/sources.go

@@ -2,6 +2,7 @@ package allanime
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -41,28 +42,28 @@ func (c *AllAnimeProvider) GetEpisodeSources(ctx context.Context, showID string,
 
 	data, ok := result["data"].(map[string]any)
 	if !ok {
-		return nil, fmt.Errorf("invalid source response")
+		return nil, errors.New("invalid source response")
 	}
 
 	rawSourceURLs, ok := data["episode"].(map[string]any)
 	if !ok {
-		return nil, fmt.Errorf("invalid episode response")
+		return nil, errors.New("invalid episode response")
 	}
 
 	sourceURLs, ok := rawSourceURLs["sourceUrls"].([]any)
 	if !ok || len(sourceURLs) == 0 {
-		return nil, fmt.Errorf("no source urls")
+		return nil, errors.New("no source urls")
 	}
 
 	references := buildSourceReferences(sourceURLs)
 	if len(references) == 0 {
-		return nil, fmt.Errorf("no source references")
+		return nil, errors.New("no source references")
 	}
 
 	out := c.resolveSourceReferences(ctx, references)
 
 	if len(out) == 0 {
-		return nil, fmt.Errorf("no playable sources extracted")
+		return nil, errors.New("no playable sources extracted")
 	}
 
 	return out, nil
@@ -261,7 +262,7 @@ func (c *AllAnimeProvider) graphqlRequestWithHash(ctx context.Context, showID, e
 
 	data, ok := parsed["data"].(map[string]any)
 	if !ok {
-		return nil, fmt.Errorf("no data in response")
+		return nil, errors.New("no data in response")
 	}
 
 	decrypted, err := responseFromTobeparsed(data)
@@ -276,7 +277,7 @@ func (c *AllAnimeProvider) graphqlRequestWithHash(ctx context.Context, showID, e
 		return parsed, nil
 	}
 
-	return nil, fmt.Errorf("no usable data in response")
+	return nil, errors.New("no usable data in response")
 }
 
 func newEpisodeHashRequest(ctx context.Context, showID, episode, mode string) (*http.Request, error) {