fix: bump cactus parser chart version and disable OTel metric pushing by default

[shuninghuang]

when opentelemetry dependency is disabled, application should not even try to export traces to it.
so we wont be spammed by errors

[Copilot]

Pull request overview

This PR adds the ability to disable OpenTelemetry tracing to prevent error spam when the OpenTelemetry dependency is disabled. It introduces an OTEL_ENABLED environment variable set to false by default for both cactus-backend and cactus-parser components.

Changes:

• Added OTEL_ENABLED: false environment variable to control OpenTelemetry tracing
• Updated cactus-backend chart version from 0.5.10 to 0.5.11
• Updated cactus-parser dependency version from 0.0.3 to 0.0.5

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
charts/cactus-backend/values.yaml	Added OTEL_ENABLED: false to both cactus-backend and cactus-parser environment variables
charts/cactus-backend/README.md	Added upgrade documentation for version 0.5.11 explaining the new OTEL_ENABLED feature
charts/cactus-backend/Chart.yaml	Bumped chart version to 0.5.11 and cactus-parser dependency to 0.0.5

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[dataviruset]

Now we have the override in two places but it's fine, it just shows what's possible to configure, it's a convenience