Context

Follow-up from PR #7053 review. Parent tracking issue: #7112

PR Conversations

• Consider reference() for KeyVault secret params (@tg-msft)
• Extract string-to-typed-value conversion to util package (@tg-msft)

What needs to change

1. Reusable util: Extract the string-to-typed-value conversion logic (currently in local_preflight.go) into a reusable util package — this functionality is likely needed elsewhere in azd.
2. KeyVault reference(): Consider using reference(resourceId(...)) syntax for KeyVault secret parameter values instead of empty strings. This could make interpreting validation errors on missing params easier to understand. Also consider a future validation rule to verify that referenced secrets actually exist.

Files to update

• cli/azd/pkg/infra/provisioning/bicep/local_preflight.go (lines ~420-431)
• New util package (TBD)