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# Type of request: This is a ...

[x ] bug report
[ ] feature request

# Detailed description

Not able to use the edge service to write metric data to cloudwatch via the javascript aws-sdk.

However, It **DOES** work when using the deprecated cloudwatch port.

## Expected behavior

Metric data to be visible when calling `awslocal cloudwatch list-metrics`

## Actual behavior

404 from edge service. No metric data is persisted, localstack instance logs the following info:

```
INFO:localstack.services.edge: Unable to determine forwarding port for API "monitoring" - please make sure this API is enabled via the SERVICES configuration
```

# Steps to reproduce

Run JS code in "Client code" section.
See 404 Error

## Command used to start LocalStack

`TMPDIR=/tmp/localstack docker-compose up`

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

```js
const AWS = require('aws-sdk')
const cw = new AWS.CloudWatch({
  endpoint: 'http://localhost:4566',
})

const data = {
  Namespace: 'ns',
  MetricData: [
    {
      MetricName: 'metric-name',
      Timestamp: new Date(),
      Value: 12345,
      Unit: 'Milliseconds',
      Dimensions: [
        { Name: 'Environment', Value: 'local' },
      ]
    }
  ]
}

cw.putMetricData(data, (err, data) => {
  if (err) {
      console.log('Error', err)
  } else {
      console.log('Success', JSON.stringify(data))
  }
})
```

if(to_bytes('key=') in data_bytes):
        return True
    if(to_bytes('Content-Disposition: form-data') in data_bytes and to_bytes('name="key"') in data_bytes):
        return True
    return False
def get_port_from_custom_rules(method, path, data, headers):
    """ Determine backend port based on custom rules. """
    
    if 'AWSAccessKeyId=' in path or 'Signature=' in path:
        return config.PORT_S3
    
    if re.match(r'^/queue/[a-zA-Z0-9_-]+$', path):
        return config.PORT_SQS
    data_bytes = to_bytes(data or '')
    if path == '/' and to_bytes('QueueName=') in data_bytes:
        return config.PORT_SQS
    
    stripped = path.strip('/')
    if method in ['GET', 'HEAD'] and '/' in stripped:
        
        return config.PORT_S3
    if stripped and '/' not in stripped:
        if method == 'PUT':
            
            return config.PORT_S3
        if method == 'POST' and is_s3_form_data(data_bytes):
            
            return config.PORT_S3
def get_service_port_for_account(service, headers):