feat(health): register LlamaServerHealthProbe (A§4)

Wire the built-but-unregistered LlamaServerHealthProbe (266bbf0) into the health monitor:
when a `llamacpp` provider URL is configured, add an HttpLlamaLivenessClient-backed probe
(dedicated CIO client, 3s per-ping timeout, shutdown-hook close) to the probe list. Gated
on a configured provider URL so a model-less box never reports a spurious LLAMA_SERVER
DEGRADED. Replaces the Main.kt TODO(wiring). main() is not unit-tested; the probe + client
are already covered by 266bbf0 — compile + :apps:server:test + detekt green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/server/src/main/kotlin/com/correx/apps/server/Main.kt

@@ -96,6 +96,9 @@ import java.nio.file.Paths
 
 private val log = LoggerFactory.getLogger("com.correx.apps.server.Main")
 
+/** Per-ping timeout (ms) for the llama-server health probe — short so a hung server never stalls it. */
+private const val LLAMA_HEALTH_TIMEOUT_MS = 3_000L
+
 fun main() {
     log.info("=== correx server starting ===")
     log.info("  port         : 8080")
@@ -438,9 +441,21 @@ fun main() {
             val seeded = DefaultEventReplayer(eventStore, com.correx.apps.server.health.HealthProjection())
                 .rebuild(com.correx.apps.server.health.SYSTEM_SESSION)
                 .subjects.mapValues { it.value.status }
+            // Monitor the llama server only when a llamacpp provider URL is configured — otherwise the
+            // LLAMA_SERVER subject would report a spurious DEGRADED on a box that runs no local model.
+            // A dedicated short-timeout client keeps a hung server from stalling the probe loop.
+            val llamaProbe = correxConfig.providers.firstOrNull { it.type == "llamacpp" }?.url?.let { url ->
+                val healthHttpClient = io.ktor.client.HttpClient(io.ktor.client.engine.cio.CIO) {
+                    engine { requestTimeout = LLAMA_HEALTH_TIMEOUT_MS }
+                }
+                Runtime.getRuntime().addShutdownHook(Thread { healthHttpClient.close() })
+                com.correx.apps.server.health.LlamaServerHealthProbe(
+                    com.correx.apps.server.health.HttpLlamaLivenessClient(healthHttpClient, url),
+                )
+            }
             com.correx.apps.server.health.HealthMonitor(
                 eventStore = eventStore,
-                probes = listOf(
+                probes = listOfNotNull(
                     com.correx.apps.server.health.DiskWatermarkProbe(
                         monitoredPaths = listOf(dataDir),
                         warnBytes = hc.diskWarnBytes,
@@ -450,9 +465,7 @@ fun main() {
                         eventStore,
                         hc.eventStoreWarnLatencyMs,
                     ),
-                    // TODO(wiring): register LlamaServerHealthProbe once an HttpClient + tokens/sec telemetry are
-                    // exposed to the health-monitor scope (currently only built inside
-                    // InfrastructureModule.createModelManager).
+                    llamaProbe,
                 ),
                 intervalMs = hc.intervalMs,
                 initialStatuses = seeded,