Surface raw RCON reply bytes + Probe RCON button

"unparseable reply (34 bytes)" told us Plutonium answered but hid the
actual bytes, forcing another guess-and-check round. rconStatusResult
now emits a formatRawReply() hex + ASCII dump of the raw UDP payload on
every bad-reply, persisted in a new last_reply_snippet column so it
survives page loads.

Wrong-password detection widens beyond the "bad rcon" phrasing to
"(bad|invalid|wrong)…(rcon|password|pass)"; print-body replies that
don't match get their first non-header line surfaced verbatim so at
least *some* server-supplied text reaches the UI.

Probe RCON button (POST /api/servers/[name]/probe-rcon) fires the same
code path as the periodic sweep on demand, cuts the RCON iteration loop
from 30s per attempt to sub-second, and refreshes the header/roster/
health when it succeeds. Snippet <details> auto-opens on bad-reply so
the bytes are one glance away.

migrateServers() picks up the new column automatically via the
introspection path added last commit.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/routes/servers/[name]/+page.svelte

@@ -42,6 +42,20 @@
         error?: string;
     }
 
+    interface RconProbeResult {
+        ok: boolean;
+        endpoint?: { host: string; port: number } | null;
+        reason?: RconFailure;
+        detail?: string;
+        rawReply?: string;
+        status?: {
+            players: number;
+            map: string | null;
+            gametype: string | null;
+            roster: RosterPlayer[];
+        };
+    }
+
     interface Server {
         name: string;
         komodo_type: string;
@@ -58,6 +72,7 @@
         roster: RosterPlayer[] | null;
         health: Health;
         endpoint: RconEndpoint | null;
+        replySnippet: string | null;
         held: Array<{ target: string; slug: string }>;
     }
     interface Integrations {
@@ -78,6 +93,12 @@
     let integrations = $state<Integrations | null>(null);
     let history = $state<DeploymentRow[]>([]);
     let name = $derived($page.params.name ?? '');
+    let komodoProbe = $state<KomodoProbeResult | null>(null);
+    let probing = $state(false);
+    let netDiagnosis = $state<NetDiagnosis | null>(null);
+    let diagnosing = $state(false);
+    let rconProbe = $state<RconProbeResult | null>(null);
+    let probingRcon = $state(false);
 
     onMount(async () => {
         const [srvRes, depRes] = await Promise.all([fetch('/api/servers'), fetch('/api/deployments')]);
@@ -101,6 +122,9 @@
     let decoded = $derived(decodeRconError(effectiveErr));
     let effectiveReason = $derived<RconFailure | null>(liveReason ?? decoded?.reason ?? null);
     let errorDetail = $derived(decoded?.detail ?? effectiveErr ?? '');
+    let effectiveSnippet = $derived<string | null>(
+        rconProbe?.rawReply ?? live?.replySnippet ?? server?.replySnippet ?? null
+    );
 
     function ago(iso: string | null): string {
         if (!iso) return 'never';
@@ -116,11 +140,6 @@
         return `${ep.host}:${ep.port}`;
     }
 
-    let komodoProbe = $state<KomodoProbeResult | null>(null);
-    let probing = $state(false);
-    let netDiagnosis = $state<NetDiagnosis | null>(null);
-    let diagnosing = $state(false);
-
     async function probeKomodo(): Promise<void> {
         if (probing || !name) return;
         probing = true;
@@ -164,6 +183,27 @@
             diagnosing = false;
         }
     }
+
+    async function probeRcon(): Promise<void> {
+        if (probingRcon || !name) return;
+        probingRcon = true;
+        rconProbe = null;
+        try {
+            const res = await fetch(`/api/servers/${encodeURIComponent(name)}/probe-rcon`, {
+                method: 'POST'
+            });
+            rconProbe = (await res.json()) as RconProbeResult;
+            // Refresh the server row so the header, roster, and health decay
+            // reflect what the probe just wrote.
+            const srvRes = await fetch('/api/servers');
+            const srvBody = (await srvRes.json()) as { servers: Server[]; integrations: Integrations };
+            server = srvBody.servers.find((s) => s.name === name) ?? server;
+        } catch (err) {
+            rconProbe = { ok: false, reason: 'send-error', detail: (err as Error).message };
+        } finally {
+            probingRcon = false;
+        }
+    }
 </script>
 
 {#if server}
@@ -223,6 +263,33 @@
                 </div>
             {/if}
 
+            {#if effectiveSnippet}
+                <details class="snippet-details" open={effectiveReason === 'bad-reply'}>
+                    <summary>raw reply ({effectiveSnippet.split('\n').length - 1} lines)</summary>
+                    <pre class="snippet">{effectiveSnippet}</pre>
+                </details>
+            {/if}
+
+            {#if effectiveEndpoint}
+                <div class="probe-row">
+                    <button class="probe-btn" onclick={probeRcon} disabled={probingRcon}>
+                        {probingRcon ? 'probing rcon…' : 'probe rcon'}
+                    </button>
+                    <span class="probe-hint">Send a fresh RCON getstatus to {effectiveEndpoint.host}:{effectiveEndpoint.port} now.</span>
+                </div>
+            {/if}
+
+            {#if rconProbe?.ok}
+                <div class="probe-result probe-ok">
+                    <span class="probe-tag ok">connected</span>
+                    <span class="probe-detail">
+                        {rconProbe.status?.players ?? '?'} players
+                        {#if rconProbe.status?.map} · map <strong>{rconProbe.status.map}</strong>{/if}
+                        {#if rconProbe.status?.gametype} · {rconProbe.status.gametype}{/if}
+                    </span>
+                </div>
+            {/if}
+
             {#if !effectiveEndpoint && integrations.komodo}
                 <div class="probe-row">
                     <button class="probe-btn" onclick={probeKomodo} disabled={probing}>