feat(remix_cli): ship Fortal as an application-owned preset

[leoafarias]

Description

This native GitHub stack contains #177, #180, and #178, from bottom to top.
This PR targets #177. The Sidebar PR #178 follows this PR.

Applications can install the Fortal theme and recipes with remix init --preset fortal.
They own the installed source and depend on Remix for behavior.

The repository retains analyzed Fortal source and derives the bundled templates from it.
Schema 1 projects retain the default preset. Recipes accept an instance style override.

This PR prepares Remix beta.9 and requires that version in both registries.
Published versions through beta.8 lack the exported types required by generated Fortal adapters.
CI installs both presets with checkout Remix. CLI publication requires hosted consumer checks.
The release instructions include CLI bootstrap and the later Fortal discontinuation.

The CLI validation and Windows fixes in #177 also apply to this preset.

Fresh Flutter applications exposed nine lint findings in copied Fortal theme source.
The theme now uses inherited fields with typed getters and unnamed library declarations.
The source generator and bundled templates match, and the consumer fixture enforces the relevant lint rules.

The guide now documents schema 2, checkout installation, preset differences, token mapping, and generated-code lint exclusions.
It also explains scope placement below the application host and default dialog centering.

Related Issues

Related to #177 and #178.

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Checklist

• My PR includes unit or integration tests for all changed behaviors.
• I have updated the relevant documentation.
• I am prepared to follow up on review comments.

Validation

• 86 CLI tests passed on the complete stack, including rejection of unsupported Remix versions before source writes.
• 407 Fortal package tests and Fortal package analysis passed.
• The Fortal checkout fixture passed analysis and three tests with stronger lint rules.
• Fortal template derivation, Radix parity, and generated source checks passed.
• Documentation validation passed for 38 MDX files and 137 Dart examples.
• Two fresh sample projects completed CLI installation, analysis, four behavior tests each, and release web builds.
• VS Code web and Chrome verified recipe customization, form behavior, theme switching, and dialog confirmation.
• Byte comparisons verified source preservation for dry-run, diff, and ordinary add. Button overwrite preserved the edited theme.
• Current GitHub CI checks 68c78e2f2, including both preset consumers and the real Windows SDK test.

Breaking Change

• Yes. The repository stops publishing new remix_fortal versions.
• No.

Existing published Fortal versions remain available. Package discontinuation follows successful hosted CLI validation.
This PR does not publish packages or discontinue Fortal.