feat: remove .metadata.image from schema (#2606)

## Description
This was a field reserved for the, now deprecated, Zarf UI 

## Checklist before merging

- [ ] Test, docs, adr added or updated as needed
- [ ] [Contributor Guide
Steps](https://github.com/defenseunicorns/zarf/blob/main/.github/CONTRIBUTING.md#developer-workflow)
followed

src/types/package.go

@@ -47,7 +47,6 @@ type ZarfMetadata struct {
  Description string `json:"description,omitempty" jsonschema:"description=Additional information about this package"`
  Version string `json:"version,omitempty" jsonschema:"description=Generic string set by a package author to track the package version (Note: ZarfInitConfigs will always be versioned to the CLIVersion they were created with)"`
  URL string `json:"url,omitempty" jsonschema:"description=Link to package information when online"`
- Image string `json:"image,omitempty" jsonschema:"description=An image URL to embed in this package (Reserved for future use in Zarf UI)"`
  Uncompressed bool `json:"uncompressed,omitempty" jsonschema:"description=Disable compression of this package"`
  Architecture string `json:"architecture,omitempty" jsonschema:"description=The target cluster architecture for this package,example=arm64,example=amd64"`
  YOLO bool `json:"yolo,omitempty" jsonschema:"description=Yaml OnLy Online (YOLO): True enables deploying a Zarf package without first running zarf init against the cluster. This is ideal for connected environments where you want to use existing VCS and container registries."`

zarf.schema.json

@@ -1018,10 +1018,6 @@
  "type": "string",
  "description": "Link to package information when online"
  },
- "image": {
- "type": "string",
- "description": "An image URL to embed in this package (Reserved for future use in Zarf UI)"
- },
  "uncompressed": {
  "type": "boolean",
  "description": "Disable compression of this package"