[MelbourneDeveloper]

Consolidates every open SharpLsp branch into one, per the one-feature-branch rule.

What's in it

• Test Explorer (Test Explorer must default test builds to Debug with shared configuration #429): test builds default to Debug and build only the selected project graph, incrementally. The tree refreshes after builds, and every test host a debug run owns is stopped. Reactive discovery contains failures: a target that cannot be listed becomes an error row with a logged warning, never an unhandled rejection.
• Diagnostics: solution-wide accuracy, freshness, cancellation and reactive refresh for C# and F#, with restore convergence, sidecar-restart recovery, severity and per-file limits and project filters. No result reports clean before the compiler is ready (Use compiler-owned projects in diagnostic protocol smoke tests #471, Resolve compiler apphost aliases in recovery fixtures #472).
• Analyzer diagnostics ([Bug]: C# LSP does not report diagnostics from external analyzers such as StyleCop #343): IDE code-style rules and external analyzers such as StyleCop now report in the editor. Each diagnostic carries its rule's documentation link (codeDescription), in C# and in F# (FSharpLint).
• Watched-file reloads run on a background worker, so requests never wait behind a compiler load:
  • Each compiler reopens the workspace it last opened. A reload never reopens a superseded or settings-replaced selection.
  • A reload replays the buffers the compiler's previous graph owned, so owners adopted for open files survive, and documents an explicit selection excluded stay excluded.
  • Restore outputs a compiler's own open wrote are not reloaded again, and a reload never restores again, so restores cannot feed reload storms.
  • A completed reload or disk sync retires the identities that racing pulls minted.
  • Only the compilers whose loaded graph a change concerns reload; a project no compiler loaded reloads none.
• Restore gate: stale assets are restored before a workspace opens. Inputs include inherited props, central package versions, NuGet configuration and global.json, including a remembered input that has since been deleted. dotnet children resolve the SDK their workspace selects instead of inheriting the C# sidecar's MSBuild registration, and every restore stage is bounded at two minutes.
• F#:
  • Wildcard <Compile> items come from MSBuild evaluation ([Bug]: F# Bad wildcard support #455).
  • A superseded owner adoption never joins a replacement workspace.
  • Script diagnostics track current references, completion resolution goes back to FCS, and function symbols are classified.
  • A design-time build whose project is deleted while it runs is abandoned at once, instead of holding every F# request for three minutes.
• C# owner adoption: a project loaded for a file outside the workspace loads under the path its restore recorded. Loading it under another spelling (a Windows drive letter in the other case, or a link) rewrote its obj inputs, so the user's next build recompiled it.
• Compiler recovery: a respawned compiler is restored without a selected workspace that no longer exists (a deleted scratch solution), instead of failing and respawning forever, and with it again once it is back.
• Debugger: a disconnect the adapter exits before answering is answered by the router. On Windows netcoredbg exits as its debuggee ends, and VS Code held the dead session until its own timeout.
• Push clients: a framework switch publishes its diagnostics before it is announced, even when other pushes compete.
• CI:
  • The SDK diagnostic suites have their own chunk.
  • Fixtures build as users' projects, outside SharpLsp's lint policy.
  • Failing Rust shards keep their sidecar logs, and every VS Code shard keeps the server's and sidecars' logs.
• Merged branches:
  • main.
  • chore/netfx-run-exit-flake: the .NET Framework run proof, already on this branch.
  • feature/397-razor-phase4: squash-merged into main as Razor: Pages and MVC, F# in Razor, editing features, collocated files, WebAssembly debugging and Hot Reload #422, then recorded with -s ours because its remaining diff was superseded here.
  • dependabot-upgrades: all grouped bumps.
• lspkit: points at lspkit main (53fd4c6, Let engine changes refresh pulls without superseding them; refuse non-.NET targets before connecting lspkit#30). Pull revisions separate supersession from engine generations, and the .NET profiler refuses non-.NET targets before connecting.

An adversarial review of this branch found eight defects (one critical, five high, one medium, one low). Each is fixed here behind a test that failed first.

Test plan

• CI green on every leg