fix: endpoint fix

pom.xml

src/frontend/grammar-manager-app/src/App.css

src/frontend/grammar-manager-app/src/App.tsx

...frontend/grammar-manager-app/src/components/FileInput.tsx

...ontend/grammar-manager-app/src/components/FileOneView.tsx

src/frontend/grammar-manager-app/src/components/FileView.tsx

...ava/com/jakubu9333/grammarManager/api/FilesControler.java

...ava/com/jakubu9333/grammarManager/model/FileMetadata.java

...ain/java/com/jakubu9333/grammarManager/model/Grammar.java

...va/com/jakubu9333/grammarManager/service/FileService.java

...va/com/jakubu9333/grammarManager/service/RuleService.java

...com/jakubu9333/grammarManager/FileGrammarServiceTest.java

...va/com/jakubu9333/grammarManager/FilesControllerTest.java

...t/java/com/jakubu9333/grammarManager/RuleServiceTest.java