[46] parallel filesystem convention example

[TomStrepsil]

Issue

resolves #46

Details

Provide an example, within the expressjs harness, demonstrating a filesystem convention (enabled by #54) whereby features exist as parallel filesystems that "patch" modules on the mainline.

Include variations of:

• files containing only constants
• css modules
• redux slices
  • all of the above use an objectProxyTogglePoint using a Proxy to retarget access to appropriate variations at access-time
• react components
  • uses the default toggle point from the react-pointcuts package
• redux reducer maps
  • a basic higher-order function toggle point, reliant on a getReducerMap factory function as the control

...to demonstrate potential toggle point configuration for these. The README.md for the example explains further.

To demonstrate the use of valtio (previously only mentioned in passing in the features package docs), this is used to make a reactive features store on the browser.

Scout Rule

• updated to v5 of upload-artifact and download-artifact GitHub Actions

• convert deprecated unstable_config_lookup_from_file to v10_config_lookup_from_file now that its stable awaiting next major version.

• upgrade eslint to 9.38.0

• change the "config example" to use "I am" rather than "I'm" after a weird playwright failure with the "large config" example that no longer rendered the html entity for the apostrophe properly. Not gonna fight it.

• update @playwright/test to 1.56.0

Screenshots

3x button click:

change to "feature 1":

2x button click:

change to "feature 2":

click "⛓️‍💥"

change to "feature 3":

4x button click:

change to "feature 4":

reload, with "feature2" header, then change to "feature 5":

CheckList

• PR starts with [ISSUE_ID].
• Has been tested (where required) before merge to main.

[Copilot]

Pull Request Overview

This PR updates dependencies and configurations across the monorepo, primarily focused on upgrading ESLint, @playwright/test, Next.js, and converting from deprecated ESLint flags.

• Updated ESLint from ^9.15.0 to ^9.38.0 and converted deprecated unstable_config_lookup_from_file flag to v10_config_lookup_from_file
• Updated @playwright/test from ^1.49.0 to ^1.56.0 across all packages
• Updated Next.js from ^15.3.0 to ^15.5.6
• Added new parallel-folder-convention example code in express example
• Updated various package versions in lock file
• Added missing TypeScript configuration and eslint comment to disable workspace warnings

Reviewed Changes

Copilot reviewed 88 out of 91 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
package.json	Updated eslint version and other root dependencies
package-lock.json	Comprehensive dependency version updates across packages
test/automation/package.json	Updated @playwright/test version
test/automation/docs/CHANGELOG.md	Documented @playwright/test upgrade
packages/webpack/package.json	Updated eslint flag in lint script
packages/webpack/docs/CHANGELOG.md	Documented eslint flag update and documentation fixes
packages/webpack/docs/README.md	Updated technical documentation references
packages/ssr/package.json	Updated eslint flag in lint script
packages/ssr/docs/CHANGELOG.md	Documented eslint flag update
packages/react-pointcuts/src/withToggledHookFactory/index.js	Simplified empty block comment
packages/react-pointcuts/package.json	Updated eslint flag in lint script
packages/react-pointcuts/docs/CHANGELOG.md	Documented eslint flag update and linebreak revert
packages/features/package.json	Updated eslint flag in lint script
packages/features/docs/CHANGELOG.md	Documented eslint flag update
examples/serve/package.json	Updated eslint flags and @playwright/test version
examples/serve/docs/CHANGELOG.md	Documented changes
examples/next/package.json	Updated Next.js and @playwright/test versions
examples/next/playwright.config.ts	Added eslint disable comment
examples/next/docs/CHANGELOG.md	Documented updates
examples/next/README.md	Removed outdated caveat about issue #50
examples/express/webpack.config.js	Added extensive TypeScript configuration
examples/express/src/routes/parallel-folder-convention/*	Added new example code files for parallel folder convention

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[Copilot]

The date format appears to be incorrect. '2025-10-21' uses an invalid month '10' (October) which only has 31 days max, but this should likely be October 21st. However, more critically, the year 2025 combined with month 10 suggests this is a future date that hasn't occurred yet relative to the current date in the codebase context.

[Copilot]

The changelog entry date '2025-10-22' represents a future date that hasn't occurred yet, which is inconsistent with typical changelog practices of documenting changes that have already been made.