fix(settings): emit Windows font family names as UTF-8 (#12602)

* fix(settings): emit Windows font family names as UTF-8

Windows PowerShell 5.1 can write localized font names with the console
code page while Node always decodes stdout as UTF-8, which garbles
Korean and other non-ASCII family names in the font picker. Force
UTF-8 OutputEncoding before enumerating InstalledFontCollection (#12590).

* test(settings): assert UTF-8 pin precedes Windows font enumeration

Lock script order so OutputEncoding is set before InstalledFontCollection
enumeration, preventing a silent regression of the mojibake fix.

* refactor(settings): cut the Windows font UTF-8 pin to the standard shape

`$OutputEncoding` only governs bytes piped to a native executable's stdin;
this script pipes to ForEach-Object, so it was inert. Drop it, and drop the
script-builder export whose only consumer was a test — the one-shot
`-Command` shape now matches windows-foreground-process-rows and ssh-browse,
while the BOM-less `UTF8Encoding::new($false)` spelling matches
powershell-osc133-bootstrap and antigravity/hook-service.

The test reaches the script through the public listSystemFontFamilies path
and pins the assignment as the script's first statement, so it fails on
removal, on a stdout write above it, and on a swapped encoding.

---------

Co-authored-by: Brennan Benson <79079362+brennanb2025@users.noreply.github.com>

src/main/system-fonts.test.ts

@@ -67,6 +67,25 @@ describe('listSystemFontFamilies', () => {
     killMock.mockReset()
   })
 
+  it('sets UTF-8 stdout encoding as the first statement of the Windows font script', async () => {
+    await withPlatform('win32', async () => {
+      execFileMock.mockImplementation((_cmd, _args, _opts, cb) => {
+        cb(null, 'Consolas\n')
+        return { kill: killMock }
+      })
+      const { listSystemFontFamilies } = await import('./system-fonts')
+      await listSystemFontFamilies()
+
+      const args = (execFileMock.mock.calls[0]?.[1] ?? []) as string[]
+      const script = args[args.indexOf('-Command') + 1] ?? ''
+      // Why: match the whole statement, not a substring — anything emitted above it
+      // still leaves in the OEM code page, and a swapped encoding must not slip by.
+      expect(script.trim().split(/\r?\n/)[0]).toBe(
+        '[Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false)'
+      )
+    })
+  })
+
   it('falls back when the platform font command never exits', async () => {
     vi.useFakeTimers()
     execFileMock.mockReturnValue({ kill: killMock })

src/main/system-fonts.ts

@@ -77,7 +77,10 @@ function listLinuxFonts(): Promise<string[]> {
 }
 
 function listWindowsFonts(): Promise<string[]> {
+  // Why: PowerShell 5.1 emits redirected stdout in the OEM code page; pin UTF-8
+  // before the first name is written or localized families arrive as mojibake (#12590).
   const script = `
+[Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false)
 Add-Type -AssemblyName System.Drawing
 $fonts = New-Object System.Drawing.Text.InstalledFontCollection
 $fonts.Families | ForEach-Object { $_.Name }