encodeAsHTML is unavailable by default in Grails 3.3.8 projects but other encoders are

### Expected Behavior

As specified in the Grails 3.3.8 documentation [here](https://grails.github.io/legacy-grails-doc/3.3.8/guide/security.html#codecs), the HTML codec should come as standard, and thus should provide the encodeAsHTML method on all objects. However, I believe that for Grails 3.3.8, it is not the case.

I have created the following tests to verify that codecs work by default due to issues I am having in a project I am trying to port from Grails 2.5.6 to Grails 6.2.0. I am doing this porting in intermediate steps, so I am currently trying to port from Grails 2.5.6 to Grails 3.3.8.

I tried to create a blank project to see if the issue I was having with codecs was isolated to me, but I don't think it is. I feel that I am missing something.

Here are the tests, located in the file `src/test/groovy/EncoderTestsSpec.groovy`:

```
import spock.lang.Specification

class EncoderTestsSpec extends Specification {

def 'Ensure we can call encodeAsHTML successfully in our application'() {

expect:
'""'.encodeAsHTML() == '"<script>"'
}

def 'Ensure we can call encodeAsBase64 successfully in our application'() {

expect:
'"<script>"'.encodeAsBase64() == 'IjxzY3JpcHQ+Ig=='
}

def 'Ensure we can call encodeAsMD5 successfully in our application'() {

expect:
'"<script>"'.encodeAsMD5() == '94936c5d221680f28f4128694dfd5c3f'
}
}
```

I expect all of these tests to pass.

### Actual Behaviour

The base64 and md5 tests pass but the html test does not. I get the following error in my test output:

```
Condition failed with Exception:

'"<script>"'.encodeAsHTML() == '&quot;&lt;script&gt;&quot;'
|
groovy.lang.MissingMethodException: No signature of method: java.lang.String.encodeAsHTML() is applicable for argument types: () values: []
Possible solutions: encodeAsHex(), encodeAsSHA1(), encodeAsMD5(), encodeAsSHA256()

at EncoderTestsSpec.Ensure we can call encodeAsHTML successfully in our application(ExampleSpec.groovy:8)
Caused by: groovy.lang.MissingMethodException: No signature of method: java.lang.String.encodeAsHTML() is applicable for argument types: () values: []
Possible solutions: encodeAsHex(), encodeAsSHA1(), encodeAsMD5(), encodeAsSHA256()
... 1 more
```

### Steps To Reproduce

- Using Grails 3.3.8, create a new app with the command `grails create-app -features hibernate5 -profile web virtualhome`
- Add in the following tests in the file `src/test/groovy/ExampleSpec.groovy`.
- Run the command `grails test-app -unit` to execute the tests
```

import spock.lang.Specification

class EncoderTestsSpec extends Specification {

def 'Ensure we can call encodeAsHTML successfully in our application'() {

expect:
'"<script>"'.encodeAsHTML() == '&quot;&lt;script&gt;&quot;'
}

def 'Ensure we can call encodeAsBase64 successfully in our application'() {

expect:
'"<script>"'.encodeAsBase64() == 'IjxzY3JpcHQ+Ig=='
}

def 'Ensure we can call encodeAsMD5 successfully in our application'() {

expect:
'"<script>"'.encodeAsMD5() == '94936c5d221680f28f4128694dfd5c3f'
}
}
```

### Environment Information

I am using a Macbook air running MacOS Sonoma 14.6.1. I am running grails 3.3.8. The following commands are what I copy-paste to set up my environment:

```
jenv global 1.8.0.412
export JAVA_HOME=$(jenv javahome)
sdk install grails 3.3.8
sdk use grails 3.3.8
sdk install groovy 2.4.15
sdk use groovy 2.4.15
export GRAILS_HOME=$(dirname $(dirname $(which grails)))
export GROOVY_HOME=$(dirname $(dirname $(which groovy)))
export PATH=$JAVA_HOME/bin:$GRAILS_HOME/bin:$GROOVY_HOME/bin:$PATH
```

My application.yml file is unchanged from the default:
```
---
grails:
profile: web
codegen:
defaultPackage: virtualhome
gorm:
reactor:
# Whether to translate GORM events into Reactor events
# Disabled by default for performance reasons
events: false
info:
app:
name: '@info.app.name@'
version: '@info.app.version@'
grailsVersion: '@info.app.grailsVersion@'
spring:
main:
banner-mode: "off"
groovy:
template:
check-template-location: false

# Spring Actuator Endpoints are Disabled by Default
endpoints:
enabled: false
jmx:
enabled: true

---
grails:
mime:
disable:
accept:
header:
userAgents:
- Gecko
- WebKit
- Presto
- Trident
types:
all: '*/*'
atom: application/atom+xml
css: text/css
csv: text/csv
form: application/x-www-form-urlencoded
html:
- text/html
- application/xhtml+xml
js: text/javascript
json:
- application/json
- text/json
multipartForm: multipart/form-data
pdf: application/pdf
rss: application/rss+xml
text: text/plain
hal:
- application/hal+json
- application/hal+xml
xml:
- text/xml
- application/xml
urlmapping:
cache:
maxsize: 1000
controllers:
defaultScope: singleton
converters:
encoding: UTF-8
views:
default:
codec: html
gsp:
encoding: UTF-8
htmlcodec: xml
codecs:
expression: html
scriptlets: html
taglib: none
staticparts: none
endpoints:
jmx:
unique-names: true

---
hibernate:
cache:
queries: false
use_second_level_cache: false
use_query_cache: false
dataSource:
pooled: true
jmxExport: true
driverClassName: org.h2.Driver
username: sa
password: ''

environments:
development:
dataSource:
dbCreate: create-drop
url: jdbc:h2:mem:devDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
test:
dataSource:
dbCreate: update
url: jdbc:h2:mem:testDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
production:
dataSource:
dbCreate: none
url: jdbc:h2:./prodDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE
properties:
jmxEnabled: true
initialSize: 5
maxActive: 50
minIdle: 5
maxIdle: 25
maxWait: 10000
maxAge: 600000
timeBetweenEvictionRunsMillis: 5000
minEvictableIdleTimeMillis: 60000
validationQuery: SELECT 1
validationQueryTimeout: 3
validationInterval: 15000
testOnBorrow: true
testWhileIdle: true
testOnReturn: false
jdbcInterceptors: ConnectionState
defaultTransactionIsolation: 2 # TRANSACTION_READ_COMMITTED
```

My build.gradle file is also completely unchanged:
```
buildscript {
repositories {
mavenLocal()
maven { url "https://repo.grails.org/grails/core" }
}
dependencies {
classpath "org.grails:grails-gradle-plugin:$grailsVersion"
classpath "org.grails.plugins:hibernate5:${gormVersion-".RELEASE"}"
classpath "com.bertramlabs.plugins:asset-pipeline-gradle:2.14.8"
}
}

version "0.1"
group "virtualhome"

apply plugin:"eclipse"
apply plugin:"idea"
apply plugin:"war"
apply plugin:"org.grails.grails-web"
apply plugin:"asset-pipeline"
apply plugin:"org.grails.grails-gsp"

repositories {
mavenLocal()
maven { url "https://repo.grails.org/grails/core" }
}

dependencies {
compile "org.springframework.boot:spring-boot-starter-logging"
compile "org.springframework.boot:spring-boot-autoconfigure"
compile "org.grails:grails-core"
compile "org.springframework.boot:spring-boot-starter-actuator"
compile "org.springframework.boot:spring-boot-starter-tomcat"
compile "org.grails:grails-web-boot"
compile "org.grails:grails-logging"
compile "org.grails:grails-plugin-rest"
compile "org.grails:grails-plugin-databinding"
compile "org.grails:grails-plugin-i18n"
compile "org.grails:grails-plugin-services"
compile "org.grails:grails-plugin-url-mappings"
compile "org.grails:grails-plugin-interceptors"
compile "org.grails.plugins:cache"
compile "org.grails.plugins:async"
compile "org.grails.plugins:scaffolding"
compile "org.grails.plugins:hibernate5"
compile "org.hibernate:hibernate-core:5.1.5.Final"
compile "org.grails.plugins:gsp"
console "org.grails:grails-console"
profile "org.grails.profiles:web"
runtime "org.glassfish.web:el-impl:2.1.2-b03"
runtime "com.h2database:h2"
runtime "org.apache.tomcat:tomcat-jdbc"
runtime "com.bertramlabs.plugins:asset-pipeline-grails:2.14.8"
testCompile "org.grails:grails-gorm-testing-support"
testCompile "org.grails:grails-web-testing-support"
}

bootRun {
jvmArgs('-Dspring.output.ansi.enabled=always')
addResources = true
String springProfilesActive = 'spring.profiles.active'
systemProperty springProfilesActive, System.getProperty(springProfilesActive)
}

assets {
minifyJs = true
minifyCss = true
}
```

### Example Application

_No response_

### Version

3.3.8

Start with the reproduction in src/test/groovy/ExampleSpec.groovy and run grails test-app -unit in a Grails 3.3.8 app created with grails create-app -features hibernate5 -profile web. Compare the HTML, Base64, and MD5 codec behavior; done means all three tests pass, including encodeAsHTML().

Written by the indexing model from the issue text.