Add --features flag for setting ACS feature flags

[AlexVulaj]

Summary

Adds a --features flag to roxie deploy that provides a convenient syntax for enabling/disabling ACS feature flags without needing to create override files.

Closes #34

Note - The --features flag currently only works with operator-based deployments (the default). It does not apply feature flags when using --helm mode. Since --helm is a hidden/experimental flag with different values structure, Helm support is deferred to a future PR if needed.

Usage

# Enable/disable feature flags
roxie deploy --features +ROX_LABEL_BASED_POLICY_SCOPING

# Multiple flags with different syntaxes
roxie deploy --features +ROX_FLAG1,-ROX_FLAG2,ROX_FLAG3=true

Feature flags apply to both Central and SecuredCluster components.

How it works

Feature flags provided with --features have the highest precedence and override values from --override files and --set expressions.

Feature flags merge with existing .spec.customize.envVars by name, not by replacing the entire array. This means:

• --features +ROX_FOO will override ROX_FOO if it exists in an override file
• Other env vars from override files are preserved

Testing

Manually tested the following cases:

• Basic feature flag applies to both central and sensor
• Feature flags override values from --override files
• Smart merge preserves other env vars from override files
• Multiple flags with different syntaxes (+, -, =true/false)

[mclasmeier]

Very cool, thank you for picking this up.
I believe we can simplify in a few places, but no fundamental concerns.

[mclasmeier]

I was thinking, maybe also check if --feature-flags has been used together with --helm and if that is the case just error out, telling the user that this is not supported?

[AlexVulaj]

@mclasmeier I also added in a check to see if someone is trying to use --helm with --features and log an error. Great suggestions so far!