Make replica count configurable across all deployment templates

[qpetraroia]

Summary

This PR makes the replica count configurable across all deployment templates (Helm, Kustomize, and Manifests) instead of using hardcoded values.

Changes

• Add REPLICACOUNT variable to all deployment template draft.yaml files with proper kind: "replicaCount" validation
• Set default value to 1 replica (configurable by users, disabled prompting for seamless experience)
• Replace hardcoded replicas: 2 with {{ .Config.GetVariableValue "REPLICACOUNT" }} in deployment templates
• Update all test fixtures to use replicas: 1 to match the new default value
• Ensure consistency across all three deployment template types (Helm, Kustomize, Manifests)

Benefits

• Users can now customize replica count when generating deployments without template modification
• Consistent behavior across all deployment template types
• Follows the same pattern as other configurable variables in the project
• Maintains backward compatibility while providing flexibility
• Default of 1 replica is more appropriate for development/testing scenarios

Usage

Users can override the replica count when generating deployments:

# Use default (1 replica)
draft create deployment

# Specify custom replica count
draft create deployment --variable REPLICACOUNT=3

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Refactor

How Has This Been Tested?

Provide instructions so we can reproduce, and list any relevant details for your test configuration. Please mention if this is a breaking change which will impact consuming tool(s).

• Unit Test:
• E2E Test:
• Other Test:

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[bosesuneha]

lgtm