Add fsharp-project-structure skill

[T-Gro]

Adds skill for F# project file structure: compilation order, .fsi signature files, and common FS0039/FS0010/FS0034 fixes.

Eval results (gpt-4.1, 3 runs, judged by claude-opus-4.6):

Scenario	Baseline	With Skill	Pairwise
Add module to project	2.3/5	5.0/5	MuchBetter
Fix broken file order (FS0039)	2.7/5	4.3/5	MuchBetter
Add .fsi signature file	1.7/5	4.0/5	MuchBetter

Overall: +64.6%, significant, CI [+17.2%, +63.0%], overfitting 0.08 (low).

[Copilot]

Pull request overview

Adds a new .NET skill focused on F# .fsproj compilation ordering and signature file (.fsi) placement, along with an eval suite and fixtures to measure improvements.

Changes:

• Added fsharp-project-structure skill documentation under plugins/dotnet/skills/.
• Added eval scenarios + F# project fixtures under tests/dotnet/fsharp-project-structure/.
• Updated .github/CODEOWNERS to assign ownership for the new skill and test area.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/dotnet/fsharp-project-structure/eval.yaml	Adds 3 eval scenarios covering adding modules, fixing file order, and adding .fsi signature files.
tests/dotnet/fsharp-project-structure/OrderService/Domain.fs	Adds an F# domain model fixture for ordering/signature scenarios.
tests/dotnet/fsharp-project-structure/OrderService/Services.fs	Adds an F# services fixture referencing Domain.
tests/dotnet/fsharp-project-structure/OrderService/Program.fs	Adds an executable entry point fixture used by scenarios.
tests/dotnet/fsharp-project-structure/OrderService/OrderService.fsproj	Adds a “correctly ordered” .fsproj fixture.
tests/dotnet/fsharp-project-structure/BrokenOrder/Domain.fs	Adds a domain fixture used in the “broken order” scenario.
tests/dotnet/fsharp-project-structure/BrokenOrder/Services.fs	Adds a services fixture that will fail if compiled before Domain.fs.
tests/dotnet/fsharp-project-structure/BrokenOrder/Program.fs	Adds an entry point fixture for the broken-order project.
tests/dotnet/fsharp-project-structure/BrokenOrder/BrokenOrder.fsproj	Adds an intentionally misordered .fsproj fixture to trigger FS0039.
plugins/dotnet/skills/fsharp-project-structure/SKILL.md	Adds the new skill guidance for .fsproj ordering and .fsi rules.
.github/CODEOWNERS	Assigns code owners for the new skill and its tests.

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[ViktorHofer]

/evaluate

[github-actions]

Skill Validation Results

Skill	Scenario	Baseline	With Skill	Δ	Skills Loaded	Overfit	Verdict
dotnet-trace-collect	High CPU in Kubernetes on Linux (.NET 8)	4.0/5	5.0/5	+1.0	✅ dotnet-trace-collect; tools: skill, report_intent, view	✅ 0.18	✅
dotnet-trace-collect	.NET Framework on Windows without admin privileges	2.3/5	5.0/5	+2.7	✅ dotnet-trace-collect; tools: skill	✅ 0.18	✅
dotnet-trace-collect	.NET 10 on Linux with root access and native call stacks	1.0/5	4.3/5	+3.3	✅ dotnet-trace-collect; tools: skill	✅ 0.18	✅
dotnet-trace-collect	Memory leak on Linux (.NET 8)	3.0/5	3.3/5	+0.3	✅ dotnet-trace-collect; tools: skill, report_intent, view	✅ 0.18	✅
dotnet-trace-collect	Slow requests on Windows with PerfView	4.7/5	5.0/5	+0.3	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	❌
dotnet-trace-collect	Excessive GC on Linux (.NET 8)	4.0/5	4.7/5	+0.7	✅ dotnet-trace-collect; tools: skill	✅ 0.18	❌
dotnet-trace-collect	Hang or deadlock diagnosis on Linux	3.7/5	4.0/5	+0.3	✅ dotnet-trace-collect; tools: skill, report_intent, view	✅ 0.18	✅
dotnet-trace-collect	Windows container high CPU with PerfView	1.7/5	5.0/5	+3.3	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	✅
dotnet-trace-collect	Long-running intermittent issue with PerfView triggers	3.0/5	5.0/5	+2.0	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	✅
dotnet-trace-collect	Linux pre-.NET 10 needing native call stacks	2.0/5	5.0/5	+3.0	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	✅
dotnet-trace-collect	Windows modern .NET with admin high CPU	2.3/5	5.0/5	+2.7	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	✅
dotnet-trace-collect	Memory leak on .NET Framework Windows	3.3/5	5.0/5	+1.7	✅ dotnet-trace-collect; tools: skill, report_intent, view	✅ 0.18	✅
dotnet-trace-collect	Kubernetes with console access prefers console tools	5.0/5	4.7/5	-0.3	✅ dotnet-trace-collect; tools: skill, report_intent, view, glob	✅ 0.18	✅
dotnet-trace-collect	Container installation without .NET SDK	3.3/5	4.0/5	+0.7	✅ dotnet-trace-collect; tools: skill	✅ 0.18	✅
dotnet-pinvoke	Generate LibraryImport declaration from C header (.NET 8+)	3.7/5	5.0/5	+1.3	✅ dotnet-pinvoke; tools: skill	✅ 0.11	✅
dotnet-pinvoke	Generate LibraryImport declaration from C header (.NET Framework)	3.7/5	5.0/5	+1.3	✅ dotnet-pinvoke; tools: skill	✅ 0.11	✅
fsharp-project-structure	Add a module to an F# project	5.0/5	5.0/5	0.0	✅ fsharp-project-structure; tools: skill	✅ 0.08	✅
fsharp-project-structure	Fix broken file order causing FS0039	4.3/5	4.0/5	-0.3	⚠️ NOT ACTIVATED	✅ 0.08	❌
fsharp-project-structure	Add a signature file to define public API	5.0/5	5.0/5	0.0	✅ fsharp-project-structure; tools: skill, glob, read_bash	✅ 0.08	❌

Model: claude-opus-4.6 | Judge: claude-opus-4.6

Full results

[ManishJayaswal]

@T-Gro - can you update this PR to create a new plugin named dotnet-fsharp and add this skill to it?