SIEM login labels are not linked to their inputs #304

Problem

app/monitoring/siem/page.tsx:73-92 renders visible "Username" and "Password" labels, but nothing links them to their fields: the <label> elements have no htmlFor and do not wrap the input, and the inputs have no id. Both fields end up with no accessible name, even though the label is right there on screen.

<label className="mb-1 block font-mono text-xs text-slate-400">Username</label>
<input
  type="text"
  value={username}
  onChange={(e) => setUsername(e.target.value)}
  ...
/>

Fix

Add an id to each input and the matching htmlFor to each label.

Acceptance

Both fields expose their visible label as their accessible name (browser devtools accessibility pane, or a screen reader).