fix(create): remove memfs runtime dependency

[tannerlinsley]

Summary

• reuse the internal worker-safe memory environment for Node create flows
• keep memfs pinned as a test-only dependency
• guard the public entrypoint and package manifest against runtime memfs regressions

Why

@tanstack/create's broad memfs runtime range now pulls newly split @jsonjoy.com/fs-* packages into temporary npx installs. Generated apps never use them. The CLI still needs an in-memory environment for add-to-app and custom add-on flows, but it already ships an equivalent internal implementation.

Related: #329, #396, X report

Validation

• pnpm build
• pnpm test:unit
• pnpm test:e2e
• blank create smoke with install and Git disabled

Summary by CodeRabbit

• Improvements

  • Reduced the published runtime footprint of @tanstack/create by removing an unnecessary runtime dependency.
  • Updated the in-memory environment handling to reuse the package’s existing environment capabilities.
  • Preserved path handling and application creation behavior while simplifying internal filesystem management.

• Tests

  • Added coverage confirming the package can be imported without the removed runtime dependency.
  • Verified the dependency is retained only for development and testing.

[coderabbitai]

📝 Walkthrough

Walkthrough

The create package now reuses the edge memory environment, removes memfs from runtime dependencies, pins it as a development dependency, and adds tests for imports and package metadata.

Changes

Create memory environment

Layer / File(s)	Summary
Shared memory environment integration packages/create/package.json, packages/create/src/environment.ts, packages/create/src/file-helpers.ts	createMemoryEnvironment now delegates to the edge environment with paths resolved from process.cwd(). MemoryEnvironmentOutput is re-exported. memfs moves to pinned development dependencies, and a related comment is clarified.
Dependency regression coverage packages/create/tests/index.test.ts, .changeset/quiet-files-travel.md	Tests verify dynamic imports and confirm that memfs is only a development dependency. A patch changeset records the package changes.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Suggested reviewers: alemtuzlak

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: removing memfs from the runtime dependencies of @tanstack/create.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch taren/remove-memfs-runtime

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 ESLint

If the error stems from missing dependencies, add them to the package.json file. For unrecoverable errors (e.g., due to private dependencies), disable the tool in the CodeRabbit configuration.

packages/create/tests/index.test.ts

Parsing error: "parserOptions.project" has been provided for @typescript-eslint/parser.
The file was not found in any of the provided project(s): packages/create/tests/index.test.ts

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@packages/create/src/environment.ts`:
- Around line 126-128: Update the environment.writeFileBase64 wrapper in
createDefaultEnvironment so base64:: contents are decoded before being passed to
the shared writeFileBase64 implementation, preserving decoded binary bytes in
the memory environment; alternatively, align the edge file helper semantics
consistently while retaining decoded-write behavior.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 9b01a8ab-13a5-4944-be68-c711c18d7e27

📥 Commits

Reviewing files that changed from the base of the PR and between db108a1 and e4a4ce5.

⛔ Files ignored due to path filters (1)

• pnpm-lock.yaml is excluded by !**/pnpm-lock.yaml

📒 Files selected for processing (5)

• .changeset/quiet-files-travel.md
• packages/create/package.json
• packages/create/src/environment.ts
• packages/create/src/file-helpers.ts
• packages/create/tests/index.test.ts