feat(website): added display names for file categories

[tombch]

Addresses #4315 by adding a displayName property for both the user-submitted file category and the output metadata fields for files. Also adds the display name for the file category within the folder upload component for clarity.

Screenshot

e.g. in the 'Extra files' section when uploading, for raw_reads, the area now has a display name:

PR Checklist

• All necessary documentation has been adapted.
• The implemented feature is covered by appropriate, automated tests.
• Any manual testing that has been done is documented (i.e. what exactly was tested?)

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[claude]

Claude finished @tombch's task in 2m 11s —— View job

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Code Review

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Overall this is a clean, well-scoped change. The displayName ?? name fallback pattern is consistent with how other fields in the codebase handle optional display names. A couple of minor points below.

website/src/components/Submission/FileUpload/FolderUploadComponent.spec.tsx

The test fixture sets displayName: 'Extra Files' and the test at line 60 asserts the display name is shown. However, there's no test for the fallback case — when displayName is undefined, the component should display fileCategory.name instead. Worth adding a small test to cover that branch: Fix this →

kubernetes/loculus/templates/_common-metadata.tpl (lines ~269–274)

        - name: {{ .name }}
          {{ if .displayName }}
          displayName: {{ .displayName }}
          {{ end }}
          type: string

The unstripped {{ if ... }} / {{ end }} blocks (no - prefix) emit extra blank lines in the generated YAML. This is functionally harmless since YAML ignores blank lines in mappings, but using {{- if .displayName }} / {{- end }} would produce cleaner output, consistent with how the rest of the template handles optional fields.

Everything else looks good — the zod schema addition in config.ts follows the existing displayName: z.string().optional() pattern, the JSON schema additions in values.schema.json are accurate, and the values.yaml example is helpful.

[anna-parker]

thanks! the preview looks good!