fix(desktop): parse user@host[:port] typed into the SSH host field

normalizeSshConfig only trimmed the host, so user@host worked only by accident
(passed through as the literal target) and user@host:port did not split into
host + port. Worse, typing user@host AND filling the User field could produce
user@user@host.

Now: split a leading user@ and a trailing :port off the host field; explicit
user/port fields win (no doubling); IPv6 literals (multiple colons) and bare
~/.ssh/config aliases are left untouched. Tests cover user@host, user@host:port,
explicit-fields-win, and the alias/IPv6 passthrough.

apps/desktop/electron/connection-config.cjs

@@ -281,14 +281,37 @@ function normalizeSshConfig(entry) {
   if (!entry || typeof entry !== 'object' || entry.mode !== 'ssh') {
     return null
   }
-  const host = String(entry.host || '').trim()
+  let host = String(entry.host || '').trim()
+  if (!host) {
+    return null
+  }
+  // Parse a user@host[:port] target typed into the single host field. Explicit
+  // user/port fields win, so filling the User field after typing user@host does
+  // NOT double up into user@user@host. A bare ~/.ssh/config alias is preserved.
+  let parsedUser
+  let parsedPort
+  const at = host.indexOf('@')
+  if (at > 0) {
+    parsedUser = host.slice(0, at)
+    host = host.slice(at + 1)
+  }
+  // Only split a trailing :port when there's exactly one colon and a numeric
+  // suffix — leaves IPv6 literals (multiple colons) and bare aliases alone.
+  if ((host.match(/:/g) || []).length === 1) {
+    const [h, p] = host.split(':')
+    if (/^\d+$/.test(p)) {
+      host = h
+      parsedPort = Number.parseInt(p, 10)
+    }
+  }
   if (!host) {
     return null
   }
   const out = { mode: 'ssh', host }
-  const user = String(entry.user || '').trim()
+  const user = String(entry.user || '').trim() || parsedUser || ''
   if (user) out.user = user
-  const port = Number.parseInt(String(entry.port ?? ''), 10)
+  const explicitPort = Number.parseInt(String(entry.port ?? ''), 10)
+  const port = Number.isInteger(explicitPort) && explicitPort > 0 ? explicitPort : parsedPort
   if (Number.isInteger(port) && port > 0 && port !== 22) {
     out.port = port
   }

apps/desktop/electron/connection-config.test.cjs

@@ -430,6 +430,37 @@ test('normalizeSshConfig preserves a non-default port', () => {
   })
 })
 
+test('normalizeSshConfig parses user@host typed into the host field', () => {
+  assert.deepEqual(normalizeSshConfig({ mode: 'ssh', host: 'jonny@mac-mini' }), {
+    mode: 'ssh',
+    host: 'mac-mini',
+    user: 'jonny'
+  })
+})
+
+test('normalizeSshConfig parses user@host:port and drops a default :22', () => {
+  assert.deepEqual(normalizeSshConfig({ mode: 'ssh', host: 'jonny@box:2222' }), {
+    mode: 'ssh',
+    host: 'box',
+    user: 'jonny',
+    port: 2222
+  })
+  assert.deepEqual(normalizeSshConfig({ mode: 'ssh', host: 'box:22' }), { mode: 'ssh', host: 'box' })
+})
+
+test('normalizeSshConfig: explicit user/port win over user@host:port (no user@user@host)', () => {
+  assert.deepEqual(
+    normalizeSshConfig({ mode: 'ssh', host: 'jonny@box:2222', user: 'admin', port: 2200 }),
+    { mode: 'ssh', host: 'box', user: 'admin', port: 2200 }
+  )
+})
+
+test('normalizeSshConfig leaves a bare ~/.ssh/config alias and IPv6 literals alone', () => {
+  assert.deepEqual(normalizeSshConfig({ mode: 'ssh', host: 'mac-mini' }), { mode: 'ssh', host: 'mac-mini' })
+  // IPv6 (multiple colons) must NOT be split as host:port
+  assert.deepEqual(normalizeSshConfig({ mode: 'ssh', host: 'fe80::1' }), { mode: 'ssh', host: 'fe80::1' })
+})
+
 test('profileSshOverride returns a profile-scoped ssh descriptor or null', () => {
   const config = { profiles: { work: { mode: 'ssh', host: 'mac-mini', user: 'jonny' }, other: { mode: 'remote', url: 'http://x' } } }
   assert.deepEqual(profileSshOverride(config, 'work'), { mode: 'ssh', host: 'mac-mini', user: 'jonny' })