[Themes] Add template generation with liquid and json support

[jamesmengo]

WHY are these changes introduced?

Fixes #0000

WHAT is this pull request doing?

How to test your changes?

Post-release steps

Measuring impact

How do we know this change was effective? Please choose one:

• n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix
• Existing analytics will cater for this addition
• PR includes analytics changes to measure impact

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes

[jamesmengo]

• [Themes] Add TODOs for template generator improvements #5101
• [Themes] Remove template type flag and related functionality #5100
• [Themes] Add template generation with liquid and json support #5099 👈 (View in Graphite)
• [Themes] Add support for generating liquid and JSON section files #5090
• Feat: Generate Liquid Blocks #5088
• Add theme generation commands for blocks, sections, and templates #5081 : 1 other dependent PR (#5089 )
• Add --dev-preview flag to theme init for framework theme support #5079
• main

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[github-actions]

Unused types (3)

Filename	types
packages/theme/src/cli/services/generate/blocks.ts	BlockGeneratorOptions
packages/theme/src/cli/services/generate/sections.ts	SectionGeneratorOptions
packages/theme/src/cli/services/generate/templates.ts	TemplateGeneratorOptions

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	75.27%	8780/11664
🟡	Branches	70.57%	4280/6065
🟡	Functions	74.98%	2295/3061
🟡	Lines	75.83%	8301/10947

Test suite run success

1981 tests passing in 896 suites.

Report generated by 🧪jest coverage report action from 1bc4bba

[david-w-shopify]

I really like that if a template doesn't already exist you skip the "Name of the template" question. Good thinking there!

On that note though - if a template doesn't already exist and you generate a Liquid one, it provides a section schema. It should be empty as templates don't have schemas.

Also this is scope creep, but I deleted gift_card.liquid and generated that as a JSON template. The default content looks fine, but includes the section main-gift_card which doesn't exist in my sections folder. I wonder if we could check if such a section exists and if not, prompt to generate that too?

Another thought - I appreciate at the moment we're just appending the template name to main- for the first section in a template, but I think main-gift_card should probably be main-gift-card for a consistent naming convention. gift_card is the only liquid file required to use an underscore and I think all official themes use kebab case everywhere else.

Finally moving on from gift_card - on selecting robots, robots.txt.liquid should be generated every time

[david-w-shopify]

Since you can already use separate flags I'm not certain if this is necessary, but it would be really nice and even faster to use if I could let the cli parse my decisions from a filename

shopify theme generate template --filename=page.landing.json

[david-w-shopify]

Metaobject templates are missing

Also customers is a directory, so should have templates like customers/login