feat: Add config-based SRE Recipe Implementation

[Gan-Tu]

In this PR, we support both config-based and implementation-based SRE Recipe implementation.

Recipe Types

• The config-based SRE Recipe makes it fast to iterate and add new SRE Recipes, as discussed in the internal design review. It also helps reduce redundant, and hacky code.
• The implementation-based SRE Recipe is kept for backward compatibility and allows for complex implementation needs that config-based SRE Recipe cannot do.
• Documentations are added for both, with support for hiding/disabling recipes.

Refactoring

• Migrated all existing SRE Recipe implementation to config-based YAML recipes
• Added one dummy implementation-based recipe for future reference.
• Updated sandboxctl to support running both types of recipes, using the samesandboxctl syntax right now.
• Refactored generic, reusable shell commands to a standalone utils file, instead of putting them as static methods in (conceptually irrelevant) recipe classes.

Future Work

I have native validation tests for config-based recipes themselves during runtime as of now. Since this PR is getting too large, I plan to have a dedicated PR for adding integration tests for config validations during e2e CI and release.

Many SRE Recipes (except the one added in #817) don't have integration tests either, so tests for SRE Recipes prob deserve a new PR and teamwork for the future anyways.

Manually verified all sandboxctl sre-recipes command and sandboxctl describe still work as intended.

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