feat: display deploy-level notifications in CLI output @W-23939851@

[WillieRuemmele]

Summary

• Displays deploy-level notifications (e.g. ApexApiVersionRetirement) as a table in human-readable output
• Handles both single notification objects and arrays (SOAP API normalization via ensureArray)
• JSON output already includes notifications via the MetadataApiDeployStatus spread
• Adds 4 unit tests covering array, single object, absent, and JSON output cases

Depends on: forcedotcom/source-deploy-retrieve (SDR PR for DeployNotification type)

Work Item

@W-23939851@: Add Deploy-Level notifications to the CLI

Proof of Work

• Tests: 23 passing (0 failing)
• Type check: clean (pre-existing unrelated errors from yarn-linked @salesforce/core mismatch)

Test plan

• yarn test passes (unit tests)
• Deploy classes with retiring API versions (< v10) to an org on API 68.0+ and verify notifications appear in both JSON and table output