fix(connection): hold markerless requests to the Host fence — plain-HTTP browser reads carry no markers

Fetch-Metadata and Origin are only attached to trustworthy destinations, so
over plain HTTP a rebound page's same-origin GET (EventSource, images,
navigations) arrives with no browser markers and a readable response. Remove
the marker shortcut; non-browser clients pass the same fence via loopback,
the CLI-derived LAN IP literals, or a declared authority.

packages/client/connection/tests/node-half.spec.ts

@@ -98,14 +98,14 @@ describe('connection node half', () => {
   })
 
   it('passes loopback and declared-authority requests through to the bridge', async () => {
-    const { routes, dispose } = await mounted({ trustedHosts: ['harness.example:3080'] })
+    const { routes, dispose } = await mounted({ trustedHosts: ['harness.example:3080', '192.168.1.5'] })
     // Loopback, no browser markers (curl shape): the fence passes; the carrier
     // answers 404 for a GET unary path — proof the bridge ran.
     const loopback = fakeResponse()
     await routes[0]!.handler(fakeRequest({ host: '127.0.0.1:3080' }), loopback.response)
     expect(loopback.state.status).toBe(404)
-    // Undeclared LAN authority, no browser markers: the `--host 0.0.0.0` curl
-    // shape must reach the bridge even with an empty-by-default trust list.
+    // LAN authority declared as a port-less IP literal — the shape the CLI
+    // derives for `--host 0.0.0.0` — passes markerless curl on any port.
     const lan = fakeResponse()
     await routes[0]!.handler(fakeRequest({ host: '192.168.1.5:3080' }), lan.response)
     expect(lan.state.status).toBe(404)