chore: add Backstage catalog metadata per RFC-2024-023

[loujaybee]

This PR implements the Backstage catalog standardization requirements defined in RFC-2024-023.

Changes Made

• Created catalog-info.yaml with automated fields
• All automated fields populated based on repository analysis

What Was Automated

Field	Value	Source
metadata.name	spring-petclinic	Repository name
metadata.description	Sample Spring Boot application...	README analysis
metadata.tags	java, service, internal	pom.xml and code structure
spec.type	service	REST controllers + Thymeleaf UI
spec.lifecycle	experimental	Sample/demo application
annotations.github.com/project-slug	gitpod-samples/spring-petclinic	Git remote

Requires Manual Review

• spec.owner: Replace team:REPLACE_WITH_TEAM_NAME with the team responsible for this component
• spec.system: Replace REPLACE_WITH_SYSTEM_NAME with the system/product this belongs to (or remove if N/A)
• Visibility tag: Verify internal is correct, or change to external if exposed to external users

Validation

⚠️ Backstage entity validator (@roadiehq/backstage-entity-validator) could not be run due to npm not being available in the environment. Manual YAML syntax verification was performed.

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Please review the automated fields and complete the manual items before merging.

[loujaybee]

⚠️ Manual Action Required

While most of the catalog metadata has been populated automatically, the following fields require your input:

Required Manual Fields

spec.owner (Line 27)

• Current: team:REPLACE_WITH_TEAM_NAME
• Action needed: Replace with your team identifier (e.g., team:platform-engineering)
• See team registry for valid team names

spec.system (Line 31)

• Current: REPLACE_WITH_SYSTEM_NAME
• Action needed: Specify which product/system this component belongs to
• See system definitions or contact Platform Engineering to create a new system

Please Review

• Verify the component description accurately reflects the purpose
• Confirm the technology tags are complete
• Ensure the lifecycle state (experimental) is correct for this sample application

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Once you've completed these items, this component will be fully compliant with RFC-2024-023.