fable 5, useElmish rework

[Freymaurer]

Closes #711

• Refactors useElmish to fix some edgecases and subscription disposal Subscriptions registered are not disposed when the React component unmounts #711
• Verifies Fable 5 compatibility
• Verify argument names for [<ReactLazyComponent>] Check if we can verify argument names when using [<ReactLazyComponent>] from existing component #712
• Update template to fable 5

[Copilot]

Pull request overview

This PR updates Feliz for Fable 5, refactors React.useElmish to address unmount/StrictMode edge cases (notably subscription disposal), and enhances [<ReactLazyComponent>] to validate import-by-reference argument names at transpile time. It also adds a new .NET-based transpilation test project and updates templates/tooling for Fable 5.

Changes:

• Refactor Feliz.UseElmish lifecycle/subscription handling and add extensive regression tests for unmount/StrictMode/in-flight commands.
• Add transpile-time validation for [<ReactLazyComponent>] import-by-reference wrappers to prevent prop-name mismatches.
• Add Transpile.Tests to validate Fable transpilation success/failure patterns and update template/tooling to Fable 5.

Reviewed changes

Copilot reviewed 70 out of 71 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
tests/vitest.config.ts	Adds Vitest tag configuration for categorized tests.
tests/Transpile.Tests/TranspileUtils.fs	New helper utilities for generating/transpiling snippet projects in tests.
tests/Transpile.Tests/TranspileFailure.test.fs	Adds transpilation-failure diagnostics test coverage.
tests/Transpile.Tests/Transpile.Tests.fsproj	New .NET test project for transpilation validation.
tests/Transpile.Tests/README.md	Documents how the transpilation tests work and how to run them.
tests/Transpile.Tests/ReactLazyComponentTests/ReactLazyImportByRefSuccess.test.fs	Adds transpile-success cases for import-by-reference lazy arg-name matching.
tests/Transpile.Tests/ReactLazyComponentTests/ReactLazyImportByRefFailure.test.fs	Adds transpile-failure cases for lazy wrapper arg-name mismatch diagnostics.
tests/Transpile.Tests/ReactLazyComponentTests/ReactLazyImportByRef.SharedFixtures.fs	Shared fixtures for lazy import-by-reference transpile tests.
tests/Transpile.Tests/ReactLazyComponentTests/ReactLazyComponentSuccess.test.fs	Ensures docs-style ReactLazyComponent example transpiles and emits expected output.
tests/Transpile.Tests/ParallelIsolation.test.fs	Validates concurrent transpilation isolation.
tests/Transpile.Tests/packages.lock.json	Locks packages for the new transpilation test project.
tests/Transpile.Tests/Main.fs	Adds Expecto entrypoint for the transpilation test assembly.
tests/Transpile.Tests/JSXHtmlTranspile.test.fs	Adds JSX output-shape transpilation assertions.
tests/Globals/Test.Globals.fsproj	Includes new shared Promise test helpers in Globals tests.
tests/Globals/PromiseTest.fs	Adds deterministic promise/deferred helpers for lifecycle tests.
tests/Globals/Library.fs	Extends test globals helpers (tagged describes, message-aware expects).
tests/Feliz/ReactBindings/ReactLazyComponent/Wrappers/ByReference.fs	Adds wrapper components for import-by-reference lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Wrappers/ByPath.fs	Adds wrapper components for path-based lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Sources/TupledSource.fs	Adds tupled source component fixture for lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Sources/RecordClassSource.fs	Adds record/class payload source fixture for lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Sources/CurriedSource.fs	Adds curried source component fixture for lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Sources/AnonRecordSource.fs	Adds anonymous-record payload source fixture for lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Loading.test.fs	Adds runtime loading tests for ReactLazyComponent wrappers.
tests/Feliz/ReactBindings/ReactLazyComponent/InputArgs.test.fs	Adds runtime argument-forwarding tests for ReactLazyComponent wrappers.
tests/Feliz/ReactBindings/ReactLazyComponent/Fixtures/Models.fs	Adds shared model payload fixtures for lazy loading tests.
tests/Feliz/ReactBindings/ReactLazyComponent/Fixtures/LazyLoadWrapper.fs	Adds a shared suspense/loading harness for lazy loading tests.
tests/Feliz/Feliz.Tests.fsproj	Registers new ReactLazyComponent test fixtures/suites in Feliz tests.
tests/Feliz.UseElmish/UseElmish/Unmount/InFlightPerform.test.fs	Adds regression test for ignoring in-flight perform results after unmount.
tests/Feliz.UseElmish/UseElmish/Unmount/InFlightEitherError.test.fs	Adds regression test for ignoring in-flight error path after unmount.
tests/Feliz.UseElmish/UseElmish/Subscription/DynamicIdsDiff.test.fs	Adds regression test ensuring subscription diffing disposes only removed subs.
tests/Feliz.UseElmish/UseElmish/Subscription/DependencySwap.test.fs	Adds regression test for dependency-driven resubscribe behavior.
tests/Feliz.UseElmish/UseElmish/StrictMode/ToggleSubscriptionStress.test.fs	Adds stress test for StrictMode mount/unmount cycles and cleanup.
tests/Feliz.UseElmish/UseElmish/StrictMode/InitCmdOfEffect.test.fs	Adds regression test that init Cmd.ofEffect fires exactly once in StrictMode.
tests/Feliz.UseElmish/UseElmish/StrictMode/InFlightPromiseIsolation.test.fs	Adds regression test preventing StrictMode “ghost” promise side effects.
tests/Feliz.UseElmish/UseElmish/OnError/ProgramOverloadAmbiguity.test.fs	Adds regression test for Program overload error handler routing.
tests/Feliz.UseElmish/UseElmish/ModelDisposable/Transition.test.fs	Tests disposal behavior when model transitions to an IDisposable case.
tests/Feliz.UseElmish/UseElmish/ModelDisposable/PostUnmountDispatch.test.fs	Tests disposal idempotency when dispatch happens after unmount.
tests/Feliz.UseElmish/UseElmish/Disposal/SubscriptionThrowDoesNotBlockCleanup.test.fs	Tests that one failing subscription dispose doesn’t block other cleanup.
tests/Feliz.UseElmish/UseElmish/DispatchStability/DispatchRef.test.fs	Ensures the dispatch reference stays stable across parent rerenders.
tests/Feliz.UseElmish/UseElmish/DependencyStable/ParentRerenderInitCmd.test.fs	Ensures stable deps don’t replay init commands on parent rerenders.
tests/Feliz.UseElmish/UseElmish/DependencyChange/ReinitOnce.test.fs	Ensures dependency changes reinit exactly once for the new instance.
tests/Feliz.UseElmish/UseElmish/DependencyChange/OldPromiseIsolation.test.fs	Ensures old instance promise completion doesn’t affect new instance.
tests/Feliz.UseElmish/SubscriptionCleanup.test.fs	Adds direct regression test for subscription disposal on unmount (#711).
tests/Feliz.UseElmish/Subscription.test.fs	Reformats/updates subscription test code style and behavior assertions.
tests/Feliz.UseElmish/package.json	Updates transpile script to clear output before running tests.
tests/Feliz.UseElmish/Main.test.fs	Updates main useElmish tests and formatting/module naming.
tests/Feliz.UseElmish/Feliz.UseElmish.Tests.fsproj	Adds new UseElmish regression test files to the project.
tests/Feliz.UseElmish/CmdOfPromise.test.fs	Adds tests for Cmd.OfPromise behavior.
tests/Feliz.UseElmish/CmdOfEffect.test.fs	Adds tests for Cmd.ofEffect behavior.
tests/Feliz.Delay/Main.test.fs	Wraps a delay in RTL.act to align with React testing expectations.
src/Vitest/Library.fs	Adds TestOptions.tags and formatting adjustments.
src/Feliz/CHANGELOG.md	Adds changelog entry for the ReactLazyComponent arg-name validation.
src/Feliz.UseElmish/UseElmish.fs	Refactors core hook logic to ensure cleanup/disposal correctness.
src/Feliz.UseElmish/Fable.Elmish.CoreLogic.md	Adds reference documentation for Elmish core loop semantics.
src/Feliz.UseElmish/CHANGELOG.md	Adds changelog entry describing the refactor and #711 fix.
src/Feliz.Template/Content/.config/dotnet-tools.json	Updates template tool versions (Fable 5, Fantomas).
src/Feliz.CompilerPlugins/ReactComponent.fs	Adds lazy import-by-ref arg-name verification at transpile time (#712).
src/Feliz.CompilerPlugins/CHANGELOG.md	Adds changelog entry for the new lazy component check.
playground/src/UseElmishExample.fs	Adds a playground repro/example for subscription cleanup behavior.
playground/src/packages.lock.json	Updates playground lockfile to include Feliz.UseElmish project dependency.
playground/src/Main.fs	Updates playground app entry rendering.
playground/src/Components.fs	Updates playground UI and adds a LazyCounter example.
playground/src/CodeSplitting.fs	Expands code splitting component examples (tupled/curried/record).
playground/src/App.fsproj	Adds new source file and references Feliz.UseElmish in the playground.
Feliz.sln	Adds the new Transpile.Tests project to the solution.
docs/versioned_docs/version-2.9.0/ecosystem/03_Hooks/Feliz.UseElmish.mdx	Clarifies dependency comparison semantics for useElmish.
docs/docs/ecosystem/04_Hooks/Feliz.UseElmish.mdx	Clarifies dependency comparison semantics for useElmish.
.vscode/settings.json	Adds Tailwind + file exclude + F# formatting settings for dev workflow.
.gitignore	Ignores tests/Transpile.Tests/temp/ generated workspaces.
.editorconfig	Tweaks F# formatting rules and includes .fsx in F# settings.
.config/dotnet-tools.json	Updates repo tool versions to Fable 5.

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