[ARO-25617] Minifies shellscripts before putting them in ARM

[hawkowl]

Which issue this PR addresses:

Fixes https://redhat.atlassian.net/browse/ARO-25617

What this PR does / why we need it:

Minifies the shell scripts when generating them so that we don't hit the 81k-ish limit in custom scripts.

Test plan for issue:

Running in INT

Is there any documentation that needs to be updated for this PR?

N/A

How do you know this will function as expected in production?

Testing in INT

[Copilot]

Pull request overview

This PR introduces shell script minification in the deployment template generator to reduce the size of VMSS Custom Script Extension payloads and avoid hitting the ~81KB limit in ARM custom scripts.

Changes:

• Added a generator helper to parse and minify the composed VMSS bootstrap shell script before embedding it into ARM template expressions.
• Switched RP and Gateway VMSS template generation to use the new minification helper.
• Updated the checked-in gateway production template output and added the mvdan.cc/sh/v3 dependency (plus related module sum updates).

Reviewed changes

Copilot reviewed 4 out of 7 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
pkg/deploy/generator/resources_rp.go	Uses the new startup script creation/minification helper for RP VMSS CSE script generation.
pkg/deploy/generator/resources_gateway.go	Uses the new startup script creation/minification helper for Gateway VMSS CSE script generation.
pkg/deploy/generator/generators.go	Adds createStartupScript which minifies shell scripts using mvdan.cc/sh and enforces a size cap.
pkg/deploy/assets/gateway-production.json	Regenerated output reflecting the minified embedded startup script.
go.mod	Adds mvdan.cc/sh/v3 and updates indirect deps.
go.sum	Records checksums for the new/updated module dependencies.

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[mociarain]

LGTM

[LiniSusan]

LGTM