feat: add --include-defaults flag to list commands and document {pm} token

[IT-WIBRC]

Description

This PR introduces the --include-defaults option to the dk list and dk config list commands, allowing users to view Scaffolder's built-in, default settings and templates alongside their custom configurations.

Additionally, this PR includes updated documentation to clarify the use of the new {pm} token, which simplifies writing package manager-agnostic commands in template configurations.

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Key Changes

1. Add --include-defaults (-d) Flag

• dk list [-d | --include-defaults]: When used, the output will merge and display all available templates, including the built-in Scaffolder defaults. This provides a complete view of all templates that can be used with dk new.
• dk config list [-d | --include-defaults]: Extends the detailed configuration view to include the Default configuration source, making it easier for users to debug configuration overrides and understand what settings/templates are provided out-of-the-box.

2. Introduce and Document {pm} Token

• The special token {pm} can now be used in the location property of command-based template configurations (e.g., {pm} create next-app@latest).
• This token is dynamically replaced at runtime with the effective package manager determined by the configuration hierarchy (template-specific packageManager > global defaultPackageManager > CLI default).
• Documentation (README.md) has been updated to explain the purpose and usage of this token, promoting package manager-agnostic template definitions.

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Why This is Valuable

These changes enhance user control and transparency:

• Clarity: Users can now easily see which templates are custom, global, or system defaults.
• Flexibility: The {pm} token allows users to define template commands that automatically adapt to their preferred package manager setting.

Fixes # (issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• New and existing feature support current supported languages
• Any dependent changes have been merged and published in downstream modules

[github-actions]

Coverage Report for ./packages/devkit

Status	Category	Percentage	Covered / Total
🟢	Lines	97.4% (🎯 85%)	3038 / 3119
🟢	Statements	97.4% (🎯 85%)	3038 / 3119
🟢	Functions	95.91% (🎯 90%)	141 / 147
🟢	Branches	93.08% (🎯 85%)	660 / 709

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
packages/devkit/src/commands/index.ts	100%	100%	100%	100%
packages/devkit/src/commands/list.ts	99.09%	91.3%	100%	99.09%	121
packages/devkit/src/commands/new.ts	93.67%	87.5%	100%	93.67%	14-17, 78
packages/devkit/src/commands/config/add.ts	100%	82.35%	100%	100%
packages/devkit/src/commands/config/index.ts	100%	95.45%	100%	100%
packages/devkit/src/commands/config/list.ts	95.37%	93.54%	100%	95.37%	48-53
packages/devkit/src/commands/config/logic.ts	97.56%	95%	100%	97.56%	90-91, 141
packages/devkit/src/commands/config/remove.ts	100%	96.55%	100%	100%
packages/devkit/src/core/config/finder.ts	100%	100%	100%	100%
packages/devkit/src/core/config/loader.ts	100%	100%	100%	100%
packages/devkit/src/core/config/merger.ts	100%	100%	66.66%	100%
packages/devkit/src/core/info/info.ts	97.36%	93.75%	100%	97.36%	22-23
packages/devkit/src/core/template/annotator.ts	100%	93.75%	100%	100%
packages/devkit/src/core/template/printer.ts	93.79%	72.97%	100%	93.79%	20, 47, 50, 107-110, 123, 140
packages/devkit/src/utils/i18n/translation-loader.ts	100%	100%	100%	100%
packages/devkit/src/utils/schema/schema.ts	100%	100%	100%	100%

Generated in workflow #269 for commit c260046 by the Vitest Coverage Report Action