Add optional Version root element to Bjoern spec

[Copilot]

Adds an optional Version field to .zgr spec files for semantic versioning of specifications. When present, it surfaces in the generated Java class as a @version Javadoc tag and in AsciiDoc output immediately after the feature title.

Model & Parsing

• BjoernZGRModell: new @JsonProperty("Version") field
• Bjoern: propagates version through constructor and exposes getter/setter
• BjoernKeywords: added VERSION("Version:") so the validator accepts the keyword

Code Generation

• BjoernFeatureTestClassBuilder.addJavaDoc(): appends @version <value> only when field is non-blank

Doc Generation

• asciidoc.ftlh: renders Version: <value> after the feature title, guarded by <#if version??>

Example .zgr usage

Feature: My Feature
Version: "2.1.0"
Scenarios:
  - Scenario: ...

Generated Javadoc:

/**
 * My Feature
 * @version 2.1.0
 */
public abstract class AbstractMyFeature { ... }

Generated AsciiDoc:

= My Feature
:toc:

Version: 2.1.0

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Neues RootElement "Version"</issue_title>
<issue_description>### Anforderung
Neues Root Element "verion" hinzufügen. Dieses Feld dient zur semantischen nachvollziehbarkeit der aktuellen Version der Spezifikation

Umsetzung

1. Version in der Bjoern Spec hinzufügen. Dies als Textfeld ergänzen keine weitere semantische Prüfung erforderlich.
2. Feld ist optional
3. Im Code die Versionsnummer im Javadoc der Klasse hinterlegen als @Version
4. In den Docs die Versionsnummer nach dem Featurenamen hinterlegen
5. Jeweilige Generierung nur vornehmen wenn auch das Feld vorhanden ist</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Neues RootElement "Version" #89

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[Copilot]

Pull request overview

This PR implements issue #89 by adding an optional Version root element to Bjoern specification files (.zgr). When present, the version is included as a @version Javadoc tag in generated Java test classes and rendered after the feature title in AsciiDoc documentation output.

Changes:

• Model and parsing: Version field added to BjoernZGRModell.java (YAML model) and Bjoern.java (processed model), with BjoernKeywords.java updated so the validator accepts Version: lines in spec files
• Code generation: BjoernFeatureTestClassBuilder.java conditionally appends @version to the Javadoc block, and asciidoc.ftlh conditionally renders Version: <value> after the feature title
• Tests: New version.zgr fixture and corresponding unit tests in BjoernFeatureTestClassBuilderTest.java, AsciiDocBuildTest.java, and BjoernValidatorTest.java

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/test/resources/version.zgr	New test fixture spec with a Version field
src/main/java/de/mehtrick/bjoern/parser/validator/validations/BjoernKeywords.java	Adds VERSION("Version:") enum constant for keyword validation
src/main/java/de/mehtrick/bjoern/parser/modell/BjoernZGRModell.java	Adds Version YAML property to the raw spec model
src/main/java/de/mehtrick/bjoern/parser/modell/Bjoern.java	Adds version field to the processed model with getter/setter
src/main/java/de/mehtrick/bjoern/generator/builder/BjoernFeatureTestClassBuilder.java	Conditionally appends @version Javadoc tag when version is present
src/main/resources/asciidoc.ftlh	Conditionally renders version line in AsciiDoc output
src/test/java/de/mehtrick/bjoern/parser/BjoernValidatorTest.java	Updates expected keyword list to include Version:
src/test/java/de/mehtrick/bjoern/generator/builder/BjoernFeatureTestClassBuilderTest.java	Adds test for @version Javadoc generation
src/test/java/de/mehtrick/bjoern/asciidoc/AsciiDocBuildTest.java	Adds test for version rendering in AsciiDoc output