Preflight docs and template subcommands

[NoaheCampbell]

Description, Motivation and Context

This PR adds two new UX-focused subcommands to Preflight and aligns the v1beta3 authoring model with v1beta2, plus richer documentation output.

• Added preflight template:

  • Renders templated specs with multiple --values files and Helm-style --set overrides where the last one added will take priority over any conflicts.
  • Uses Helm engine for .Values-based templates.
  • Outputs fully resolved YAML with conditionals removed.

• Added preflight docs:

  • Accepts one or more specs; renders each with provided values and concatenates enabled analyzers’ docStrings to Markdown.
  • Multiple --values files, --set overrides, and -o output supported.
  • Markdown formatting: Title: lines → headings; sections separated by blank lines.
  • Normalizes values maps pre-merge to avoid type errors with strvals.

• v1beta3 spec shape decisions:

  • Align structure to v1beta2: spec.analyzers: [...].
  • Optional docString at the analyzer level for docs extraction.
  • Helm templating with .Values.; feature modularity via analyzer-level {{ if .Values. }} guards.
  • Added docString in order for vendors to give end customers explanations for requirements in an attempt to reduce friction points

Checklist

• New and existing tests pass locally with introduced changes.
• Tests for the changes have been added (for bug fixes / features)
• The commit message(s) are informative and highlight any breaking changes
• Any documentation required has been added/updated. For changes to https://troubleshoot.sh/ create a PR here

Does this PR introduce a breaking change?

• Yes
• No

[bennyyang11]

Just some clarification questions.

[bennyyang11]

Looks good to me.