feat: support enum flags in telemetry to log known flag values

[jongio]

Summary

Add support for "enum flags" at the cobra layer so that known flag values (not just flag names) are automatically logged in cmd.flags telemetry. This would eliminate the need for separate command-specific telemetry attributes for flags with known value sets.

Background

Currently, cmd.flags in cli/azd/cmd/middleware/telemetry.go only records flag names that were explicitly set by the user, not their values. For flags like --provider (github/azdo) and --auth-type (federated/client-credentials), separate telemetry attributes (PipelineProviderKey, PipelineAuthKey) are needed to capture the resolved values.

@weikanglim suggested in PR #7299 that we define enum flags at the cobra layer and allow known values to be logged directly, reducing duplication.

Proposed Approach

1. Add enum annotations to flag definitions — Commands with enum-like flags (e.g., --provider github|azdo, --auth-type federated|client-credentials) would annotate the flag with its known values
2. Update telemetry middleware — cmd/middleware/telemetry.go would check for enum annotations and log the value (not just the name) for annotated flags
3. Remove duplicate attributes — Once enum values flow through cmd.flags, remove the separate PipelineProviderKey, PipelineAuthKey, etc.

Scope

Files likely affected (6-12):

• cli/azd/cmd/middleware/telemetry.go — core change
• cli/azd/cmd/pipeline.go — --provider, --auth-type
• cli/azd/cmd/auth_login.go — --federated-credential-provider
• cli/azd/cmd/copilot.go — --scope, --action, --operation, --permission
• cli/azd/cmd/extension.go — extension source add --type
• cli/azd/cmd/templates.go — template source add --type
• Related tests

Precedent

cli/azd/pkg/output/parameter.go already uses flag annotations for output formats — a similar pattern could be extended.

Considerations

• Changing cmd.flags to include values has downstream cardinality implications for telemetry pipelines and Kusto queries
• Need to ensure only known/enum values are logged (not arbitrary user input) to avoid PII concerns
• Runtime-resolved values (e.g., auto-detected provider) may still need separate attributes since they're not flag values

Related

• PR feat: comprehensive telemetry audit - add command-specific usage attributes #7299 — Metrics audit (where this was identified)