[Feature] Add link type for "User Story" with a different icon

### Describe the Bug

I want to propose a new Feature.

Currently, Allure proposes a `issue` link type.

The inconvenience I have is that in my use case, I want to add links to two types of issues (bug & user story) and Allure assigns the same icon to both links

I would like to add links to "user stories" and have a different icon associated to those links.

Is it possible to add a link type named `story` with a different icon associated to it?

It would share the same link pattern of the `issue` link type

### Steps to Reproduce

Let me give you an example of how this new feature should work :

For java: add `@Story` annotation

```
class TestMyWebsite {

@Link(name = "Website", url = "https://dev.example.com/")
@Issue("AUTH-123")
@Story("AUTH-124")
@TmsLink("TMS-456")
void testAuthentication() {
// ...
}
}

```
For Python: add `@allure.story` decorator

```
@allure.link("https://dev.example.com/", name="Website")
@allure.issue("AUTH-123")
@allure.story("AUTH-124")
@allure.testcase("TMS-456")
def test_authentication():
...
```

The `story` link type will share the same link pattern of the `issue` link type, but will have a different icon associated.

### Expected Behaviour

The `story` link type will share the same link pattern of the `issue` link type, but will have a different icon associated.

### Screenshots or Additional Context

_No response_

### What Language are you using?

Java

### What Framework/Allure Integration you are using?

allure-junit5

### What version of Allure Integration you are using?

2.24.1

### What version of Allure Report you are using?

2.24.1

### Code of Conduct

- [X] I agree to follow this project's Code of Conduct

Start by tracing the existing `issue` link type from the Java `@Issue` annotation to the report icon, and compare the requested `@Story` annotation behavior. Done means Java and Python integrations accept `story`, it uses the existing issue link pattern, and the report displays a distinct icon.

Written by the indexing model from the issue text.