Say when a language has no server instead of just doing less

[Seungpyo1007]

From the 0.4.0 plan §7 — "attach more language servers". Reading the code first changed what the work was.

They were already attached

rust, go, c, cpp, shell, lua and java are all in lspRegistry.cjs and activate automatically when the binary is on PATH. Nothing needed adding.

What was actually missing

The registry only kept servers it found. So when gopls is not installed, a Go file gets syntax highlighting and nothing else — no diagnostics, no go-to-definition, no symbols — and the app never says why. It reads as the app simply being weak at Go.

There was no way to say otherwise: to report that something is missing you have to know it could exist.

The catalog now holds every server this app knows about, installed or not, with the command and how to install it. Opening a file of such a language says so once:

go 은(는) 언어 서버가 없어 하이라이트만 됩니다. gopls 를 설치하면 정의·진단·심볼이 켜집니다 — go install golang.org/x/tools/gopls@latest

Once per language, and only when a file of that language is actually opened. TypeScript is deliberately never reported as missing — Monaco's worker handles it, so saying otherwise would be false.

The decision logic is in src/engine/lspHint.ts as pure functions (11 tests), including that an unknown language is never reported.

Also

registry() runs where/which once per language synchronously, and whoever asked first paid for all of it — which turned out to be the first file open. It is now built shortly after startup instead.

Verification

Real app, on a machine with neither gopls nor rust-analyzer, 5/5: opening main.go gives the notice with the install command; app.ts stays silent; lib.rs gets its own notice; reopening main.go says nothing.

1102 unit tests passing. npm run typecheck and npm run build clean.

A probe mistake worth noting: it clicked the src folder before each file, toggling it collapsed, so most file clicks silently did nothing and the run looked like the notice never fired. Expanding once fixed the probe — the app had been correct from the first run.