feat: cross app secret referencing

[nimish-ks]

Extended the existing secret referencing system to support cross-app secret referencing.

[rohan-chaturvedi]

@nimish-ks When a reference cannot be resolved, this throws an exception:

"Error fetching secrets: Error: Failed to resolve reference ${LHC::staging.FOO}: Failed to resolve reference: Invalid environment name: staging"

This seems to diverge from the behavior of other SDKs, which leave the unresolved reference syntax in place. Lets keep the behavior consistent, but perhaps console.warn about the failed reference resolution

[nimish-ks]

@nimish-ks When a reference cannot be resolved, this throws an exception:

"Error fetching secrets: Error: Failed to resolve reference ${LHC::staging.FOO}: Failed to resolve reference: Invalid environment name: staging"

This seems to diverge from the behavior of other SDKs, which leave the unresolved reference syntax in place. Lets keep the behavior consistent, but perhaps console.warn about the failed reference resolution

Good catch. Fixed. Please retest.

[rohan-chaturvedi]

LGTM