fix(lint): staticcheck S1030, QF1002 and remove unused _ctx stub

internal/tools/pr_files_diff.go

@@ -143,7 +143,7 @@ func splitUnifiedDiff(d []byte) map[string][]byte {
 
 	flush := func() {
 		if currentFile != "" {
-			m[currentFile] = []byte(current.String())
+			m[currentFile] = current.Bytes()
 			current.Reset()
 		}
 	}

internal/tools/pr_files_diff_test.go

@@ -42,11 +42,11 @@ func buildFilesJSON(files []string, additions int) string {
 func newPRFilesDiffServer(t *testing.T, filesJSON, rawDiff string) *httptest.Server {
 	t.Helper()
 	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		switch {
-		case r.URL.Path == "/api/v1/repos/o/r/pulls/1/files":
+		switch r.URL.Path {
+		case "/api/v1/repos/o/r/pulls/1/files":
 			w.Header().Set("Content-Type", "application/json")
 			_, _ = w.Write([]byte(filesJSON))
-		case r.URL.Path == "/api/v1/repos/o/r/pulls/1.diff":
+		case "/api/v1/repos/o/r/pulls/1.diff":
 			w.Header().Set("Content-Type", "text/plain")
 			_, _ = w.Write([]byte(rawDiff))
 		default:

internal/tools/tool.go

@@ -1,7 +1,6 @@
 package tools
 
 import (
-	"context"
 	"encoding/json"
 
 	"gitea.d-ma.be/mathias/gitea-mcp/internal/registry"
@@ -21,8 +20,6 @@ func parseArgs(raw json.RawMessage, dst any) error {
 	return json.Unmarshal(raw, dst)
 }
 
-func _ctx(ctx context.Context) context.Context { return ctx } // stub for future hooks
-
 // capLimit returns a sane page size: 0 or negative → def, > 50 → 50.
 func capLimit(in, def int) int {
 	if in <= 0 {