chore: Don't mask 405 as 500 (#32829)

/ok-to-test tags="@tag.Sanity"

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Introduced handling for "HTTP method not allowed" errors to improve
user feedback on unsupported actions.

- **Refactor**
- Optimized error handling structure by using annotations and removing
outdated constructors.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java

@@ -12,6 +12,14 @@ import java.text.MessageFormat;
 public enum AppsmithError {
     // Ref syntax for message templates:
     // https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/text/MessageFormat.html
+    HTTP_METHOD_NOT_ALLOWED(
+            405,
+            AppsmithErrorCode.HTTP_METHOD_NOT_ALLOWED.getCode(),
+            "HTTP Method not allowed.",
+            AppsmithErrorAction.DEFAULT,
+            "Invalid method",
+            ErrorType.BAD_REQUEST,
+            null),
     INVALID_PARAMETER(
             400,
             AppsmithErrorCode.INVALID_PARAMETER.getCode(),

app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithErrorCode.java

@@ -4,6 +4,7 @@ import lombok.Getter;
 
 @Getter
 public enum AppsmithErrorCode {
+    HTTP_METHOD_NOT_ALLOWED("AE-APP-4001", "HTTP method not allowed"),
     INVALID_ACTION_COLLECTION("AE-ACC-4038", "Invalid action collection"),
     UNAUTHORIZED_ACCESS("AE-ACL-4003", "Unauthorized access"),
     ACL_NO_RESOURCE_FOUND("AE-ACL-4004", "Acl no resource found"),

app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/GlobalExceptionHandler.java

@@ -17,6 +17,7 @@ import io.micrometer.core.instrument.util.StringUtils;
 import io.sentry.Sentry;
 import io.sentry.SentryLevel;
 import io.sentry.protocol.User;
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.errors.LockFailedException;
@@ -28,6 +29,7 @@ import org.springframework.web.bind.annotation.ControllerAdvice;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.support.WebExchangeBindException;
+import org.springframework.web.server.MethodNotAllowedException;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.ServerWebInputException;
 import reactor.core.publisher.Mono;
@@ -44,6 +46,7 @@ import java.util.Map;
  * sending it to the client.
  */
 @ControllerAdvice
+@RequiredArgsConstructor
 @Slf4j
 public class GlobalExceptionHandler {
 
@@ -55,17 +58,6 @@ public class GlobalExceptionHandler {
 
     private final SessionUserService sessionUserService;
 
-    public GlobalExceptionHandler(
-            RedisUtils redisUtils,
-            AnalyticsService analyticsService,
-            GitFileUtils fileUtils,
-            SessionUserService sessionUserService) {
-        this.redisUtils = redisUtils;
-        this.analyticsService = analyticsService;
-        this.fileUtils = fileUtils;
-        this.sessionUserService = sessionUserService;
-    }
-
     private void doLog(Throwable error) {
         if (error instanceof BaseException baseException && baseException.isHideStackTraceInLogs()) {
             log.error(baseException.getClass().getSimpleName() + ": " + baseException.getMessage());
@@ -284,6 +276,25 @@ public class GlobalExceptionHandler {
         return getResponseDTOMono(urlPath, response);
     }
 
+    @ExceptionHandler
+    @ResponseBody
+    public Mono<ResponseDTO<ErrorDTO>> catchMethodNotAllowed(MethodNotAllowedException e, ServerWebExchange exchange) {
+        AppsmithError appsmithError = AppsmithError.HTTP_METHOD_NOT_ALLOWED;
+
+        exchange.getResponse().setStatusCode(HttpStatus.resolve(appsmithError.getHttpErrorCode()));
+
+        String urlPath = exchange.getRequest().getPath().toString();
+        ResponseDTO<ErrorDTO> response = new ResponseDTO<>(
+                appsmithError.getHttpErrorCode(),
+                new ErrorDTO(
+                        appsmithError.getAppErrorCode(),
+                        appsmithError.getErrorType(),
+                        appsmithError.getMessage(e.getMessage()),
+                        appsmithError.getTitle()));
+
+        return getResponseDTOMono(urlPath, response);
+    }
+
     /**
      * This function catches the generic Exception class and is meant to be a catch all to ensure that we don't leak
      * any information to the client. Ideally, the function #catchAppsmithException should be used