Add apply --server-side and template --live

[laxuankhanh1902]

Summary

This PR introduces two new optional features for improved CLI UX when working with Conduktor Console (requires console-plus#4510 to be released first). No breaking changes - all existing commands and flags continue to work exactly as before.

Demo: https://asciinema.org/a/dsoXluaQjn7CCqn7raknaRzIv

Why Move Logic to the Server?

1. Simpler CLI - Less logic in the client, easier to maintain
2. More control - Server handles parsing, versioning, parallelization, and logging
3. Better performance - Fewer round-trips between client and server
4. Reusable endpoints - These APIs can be leveraged for other purposes (including future LLM integrations)

Note: These are purely additive changes. The default behavior of apply and template commands remains unchanged. Users can opt-in to the new features by adding the new flags.

New Features

Server-Side Apply (--server-side)

Instead of applying resources one-by-one from the client, --server-side sends all resources in a single HTTP request and polls for status updates.

conduktor apply -f resources/ --server-side
conduktor apply -f resources/ --server-side --strategy continue-on-error
conduktor apply -f resources/ --server-side --dry-run

Benefits:

• More efficient for large numbers of resources
• Server handles ordering and dependency resolution
• Automatic retries on transient failures
• Live progress display with polling

New flags:

• --server-side: Enable server-side processing
• --strategy: fail-fast (default) or continue-on-error
• --no-progress: Disable live progress (useful for CI)
• --yes: Skip confirmation for large operations (50+ resources)

Exit codes:

• 0: All resources applied successfully
• 1: All resources failed (or error occurred)
• 2: Partial success (some succeeded, some failed)

Live Templates (--live)

Fetch templates directly from the Console server instead of using embedded defaults.

conduktor template --live                        # List available kinds from server
conduktor template Topic --live                  # Get Topic template from server
conduktor template Topic --live --cluster gw1   # Get template for specific gateway cluster

Benefits:

• Templates are always up-to-date with the server's schema
• Access to gateway-specific kinds when using --cluster (e.g., VirtualCluster, Interceptor, GatewayServiceAccount)

Backward Compatibility

Command	Without new flags	With new flags
apply -f file.yaml	✅ Works as before (client-side)	--server-side opts into server processing
template Topic	✅ Works as before (embedded)	--live opts into server templates

• All existing scripts and workflows continue to work without modification
• New flags are opt-in only
• No changes to default behavior

API Endpoints Used

• POST /public/v1/resources/batch-apply - Submit resources for server-side apply
• GET /public/v1/resources/batch-apply/{token} - Poll for apply status
• GET /public/v1/resources/template - List available template kinds
• GET /public/v1/resources/template/{kind} - Get template for specific kind