Discord: log node-reported stream state; remove a radio channel or a server

- handle_actual logs every node-reported state TRANSITION (not heartbeats)
  with stream/node/guild/channel/token ids and the node's error text: info
  for connected/connecting/stopped, warning for error, and a dedicated
  "radio bot X failed to log in on node N: <reason>" line for login_failed.
  The node's reason code is now stored in actual.code and shown next to the
  error on Settings > Discord and the node page.
- Remove a radio channel permanently: streams.delete_stream stops it through
  desired state first (node republished without it, token -> releasing per
  #216, freed on the node's ack), then deletes the doc in a transaction that
  refuses if the channel was restarted in between. DELETE
  /discord/streams/{id} (platform admin) and DELETE
  /discord/nodes/{node}/streams/{id} (admin or org owner, same org + node
  only; operators can still stop, not remove). Audited.
- Remove a server: DELETE /discord/guilds/{id} (admin) deletes every radio
  channel in it the same way, then tombstones discord_guilds (org_id None +
  unlinked_at, #218 semantics, plus removed_at) so it never falls back to
  DISCORD_UNLINKED_GUILD_ORG_ID; the admin page hides it, and /drb link or the
  admin link brings it back. Optional leave_radio_bots makes pool bots and the
  server's org's own BYO bots leave via Discord REST; the DRB server bot stays
  until kicked, and the UI says so. Audited.
- UI: Remove (with confirm) on Radio channels, Servers and the node page list.

Refs #213, #221

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

drb-frontend/components/discord/ServersPanel.tsx

@@ -10,6 +10,8 @@ import { DIM, Field, INPUT, Panel, Status, Table, TD } from "./ui";
 // radio channel without being linked (it acts for DISCORD_UNLINKED_GUILD_ORG_ID).
 // Linking is PUT /discord/guilds/{id}/link (platform admin). The owner-side
 // "/drb link code:" flow is server-26#213 item 1 and is not built here.
+// Remove is DELETE /discord/guilds/{id}: its radio channels are stopped then
+// deleted, and the server is unlinked with no fallback org.
 
 function LinkForm({
   overview,
@@ -83,6 +85,63 @@ function LinkForm({
   );
 }
 
+type RemoveResult = { guild: string; streams: number; bots: { name: string; left: boolean; error: string | null }[] };
+
+function RemoveForm({
+  guild,
+  onDone,
+  onCancel,
+}: {
+  guild: DiscordGuild;
+  onDone: (r: RemoveResult) => void;
+  onCancel: () => void;
+}) {
+  const [leaveBots, setLeaveBots] = useState(false);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const n = guild.live_streams;
+
+  async function submit() {
+    setSaving(true);
+    setError(null);
+    try {
+      const r = await c2api.removeDiscordGuild(guild.guild_id, leaveBots);
+      onDone({ guild: guildLabel(guild), streams: r.streams_removed.length, bots: r.radio_bots });
+    } catch (err) {
+      setError(parseC2Error(err).message);
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  return (
+    <div className="px-4 py-4 border-b border-line bg-raised text-xs text-ink-2 space-y-3">
+      <p>
+        <b className="text-ink">Remove {guildLabel(guild)} from DRB?</b>{" "}
+        {n > 0
+          ? `Its ${n} live radio channel${n === 1 ? " is" : "s are"} stopped first, then every radio channel in it is deleted.`
+          : "Every radio channel in it is deleted."}{" "}
+        It is unlinked and will not fall back to the default organization; linking it again brings it back.
+      </p>
+      <label className="flex items-start gap-2 cursor-pointer">
+        <input type="checkbox" className="mt-0.5" checked={leaveBots} onChange={(e) => setLeaveBots(e.target.checked)} />
+        <span>
+          Also make the radio bots leave this Discord server (the platform pool and this server&apos;s organization&apos;s
+          own bots). They need a new invite to come back.
+        </span>
+      </label>
+      <p className="text-ink-muted">
+        The DRB bot itself stays in the Discord server until someone kicks it there.
+      </p>
+      {error && <p className="text-sev-major">{error}</p>}
+      <div className="flex gap-2">
+        <Button size="sm" variant="danger" disabled={saving} onClick={submit}>{saving ? "Removing…" : "Remove server"}</Button>
+        <Button size="sm" variant="ghost" onClick={onCancel}>Cancel</Button>
+      </div>
+    </div>
+  );
+}
+
 export function ServersPanel({
   overview,
   onChanged,
@@ -92,6 +151,8 @@ export function ServersPanel({
 }) {
   // "new" = blank link form; a guild id = editing that row's link.
   const [editing, setEditing] = useState<string | null>(null);
+  const [removing, setRemoving] = useState<string | null>(null);
+  const [removed, setRemoved] = useState<RemoveResult | null>(null);
   const fallback = overview.limits.unlinked_guild_org_id;
   const fallbackName = overview.limits.unlinked_guild_org_name || fallback;
   const max = overview.limits.guild_max_streams;
@@ -119,6 +180,19 @@ export function ServersPanel({
       }
     >
       {editing === "new" && <LinkForm overview={overview} onDone={done} onCancel={() => setEditing(null)} />}
+      {removed && (
+        <div className="px-4 py-3 border-b border-line text-xs text-ink-2">
+          Removed {removed.guild}: {removed.streams} radio channel{removed.streams === 1 ? "" : "s"} deleted.
+          {removed.bots.length > 0 && (
+            <>
+              {" "}Radio bots:{" "}
+              {removed.bots.map((b) => `${b.name} ${b.left ? "left" : `did not leave (${b.error ?? "unknown error"})`}`).join("; ")}.
+            </>
+          )}{" "}
+          The DRB bot is still in that Discord server until someone kicks it.
+          <button className="ml-3 text-accent hover:underline" onClick={() => setRemoved(null)}>Dismiss</button>
+        </div>
+      )}
       {overview.guilds.length === 0 ? (
         <p className="px-4 py-6 text-sm text-ink-muted">No Discord servers yet. Link one, or run a radio command in a server the DRB bot is in.</p>
       ) : (
@@ -147,13 +221,50 @@ export function ServersPanel({
                     <Status health="bad">Unlinked</Status>
                   )}
                 </td>
-                <td className={`${TD} text-right`}>
-                  <Button size="sm" variant="secondary" onClick={() => setEditing(editing === g.guild_id ? null : g.guild_id)}>
+                <td className={`${TD} text-right whitespace-nowrap`}>
+                  <Button
+                    size="sm"
+                    variant="secondary"
+                    onClick={() => {
+                      setRemoving(null);
+                      setEditing(editing === g.guild_id ? null : g.guild_id);
+                    }}
+                  >
                     {g.linked ? "Change org" : "Link"}
                   </Button>
+                  <Button
+                    size="sm"
+                    variant="danger"
+                    className="ml-1"
+                    onClick={() => {
+                      setEditing(null);
+                      setRemoved(null);
+                      setRemoving(removing === g.guild_id ? null : g.guild_id);
+                    }}
+                  >
+                    Remove
+                  </Button>
                 </td>
               </tr>
             );
+            if (removing === g.guild_id) {
+              return [
+                row,
+                <tr key={`${g.guild_id}-remove`}>
+                  <td colSpan={6} className="p-0 border-b border-line">
+                    <RemoveForm
+                      guild={g}
+                      onCancel={() => setRemoving(null)}
+                      onDone={async (r) => {
+                        setRemoving(null);
+                        setRemoved(r);
+                        await onChanged();
+                      }}
+                    />
+                  </td>
+                </tr>,
+              ];
+            }
             if (editing !== g.guild_id) return [row];
             return [
               row,

drb-frontend/components/discord/StreamsPanel.tsx

@@ -18,6 +18,8 @@ import { DIM, Field, INPUT, InviteLinks, Panel, Status, Table, TD } from "./ui";
 // Radio channels = discord_streams docs, desired vs actual. Start/Stop/Add go
 // through the same routes the Discord bot uses (POST /discord/streams,
 // POST /discord/guilds/{id}/stop), which accept a platform-admin token.
+// Remove is DELETE /discord/streams/{id} (admin): c2-core stops the channel
+// through desired state first, then deletes it.
 
 type Invite = { name: string; invite_url: string | null }[];
 
@@ -214,7 +216,12 @@ export function StreamsPanel({
                 <td className={TD}>{s.mode === "adhoc" ? "ad-hoc" : s.mode ?? "—"}</td>
                 <td className={TD}>
                   <Status health={health}>{label}</Status>
-                  {isOn && s.actual?.error && <div className={`${DIM} mt-1 max-w-[16rem]`}>{s.actual.error}</div>}
+                  {isOn && s.actual?.error && (
+                    <div className={`${DIM} mt-1 max-w-[16rem]`}>
+                      {s.actual.error}
+                      {s.actual.code && <span className="font-mono"> [{s.actual.code}]</span>}
+                    </div>
+                  )}
                   {!isOn && s.stop_reason && <div className={`${DIM} mt-1`}>{s.stop_reason}</div>}
                   {err && (
                     <div className="text-xs text-sev-major mt-1 max-w-[16rem]">
@@ -224,7 +231,7 @@ export function StreamsPanel({
                   )}
                 </td>
                 <td className={TD}>{s.token_name ?? <span className={DIM}>—</span>}</td>
-                <td className={`${TD} text-right`}>
+                <td className={`${TD} text-right whitespace-nowrap`}>
                   {isOn ? (
                     <Button
                       size="sm"
@@ -256,6 +263,22 @@ export function StreamsPanel({
                       {busy === s.stream_id ? "Starting…" : "Start"}
                     </Button>
                   )}
+                  <Button
+                    size="sm"
+                    variant="danger"
+                    className="ml-1"
+                    disabled={busy !== null}
+                    onClick={() => {
+                      const name = s.channel_name || "this channel";
+                      const msg = isOn
+                        ? `Remove radio from ${name} permanently? It is stopped first (the node logs its radio bot out), then deleted from DRB.`
+                        : `Remove ${name} from DRB permanently?`;
+                      if (!confirm(msg)) return;
+                      act(s, () => c2api.deleteDiscordStream(s.stream_id));
+                    }}
+                  >
+                    Remove
+                  </Button>
                 </td>
               </tr>
             );