core(deploy): DeploymentStrategy enum with safe wire conversion

Typed enum (BLUE_GREEN, ROLLING) with fromWire/toWire kebab-case
translation. fromWire falls back to BLUE_GREEN for unknown or null
input so the executor dispatch site never null-checks and no
misconfigured container-config can throw at runtime.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cameleer-server-core/src/main/java/com/cameleer/server/core/runtime/DeploymentStrategy.java

@@ -0,0 +1,31 @@
+package com.cameleer.server.core.runtime;
+
+/**
+ * Supported deployment strategies. Persisted as a kebab-case string on
+ * ApplicationConfig / ResolvedContainerConfig; {@link #fromWire(String)} is
+ * the only conversion entry point and falls back to {@link #BLUE_GREEN} for
+ * unknown or null input so the executor never has to null-check.
+ */
+public enum DeploymentStrategy {
+    BLUE_GREEN("blue-green"),
+    ROLLING("rolling");
+
+    private final String wire;
+
+    DeploymentStrategy(String wire) {
+        this.wire = wire;
+    }
+
+    public String toWire() {
+        return wire;
+    }
+
+    public static DeploymentStrategy fromWire(String value) {
+        if (value == null) return BLUE_GREEN;
+        String normalized = value.trim().toLowerCase();
+        for (DeploymentStrategy s : values()) {
+            if (s.wire.equals(normalized)) return s;
+        }
+        return BLUE_GREEN;
+    }
+}

cameleer-server-core/src/test/java/com/cameleer/server/core/runtime/DeploymentStrategyTest.java

@@ -0,0 +1,34 @@
+package com.cameleer.server.core.runtime;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DeploymentStrategyTest {
+
+    @Test
+    void fromWire_knownValues() {
+        assertThat(DeploymentStrategy.fromWire("blue-green")).isEqualTo(DeploymentStrategy.BLUE_GREEN);
+        assertThat(DeploymentStrategy.fromWire("rolling")).isEqualTo(DeploymentStrategy.ROLLING);
+    }
+
+    @Test
+    void fromWire_caseInsensitiveAndTrims() {
+        assertThat(DeploymentStrategy.fromWire("BLUE-GREEN")).isEqualTo(DeploymentStrategy.BLUE_GREEN);
+        assertThat(DeploymentStrategy.fromWire("  Rolling  ")).isEqualTo(DeploymentStrategy.ROLLING);
+    }
+
+    @Test
+    void fromWire_unknownOrNullFallsBackToBlueGreen() {
+        assertThat(DeploymentStrategy.fromWire(null)).isEqualTo(DeploymentStrategy.BLUE_GREEN);
+        assertThat(DeploymentStrategy.fromWire("")).isEqualTo(DeploymentStrategy.BLUE_GREEN);
+        assertThat(DeploymentStrategy.fromWire("canary")).isEqualTo(DeploymentStrategy.BLUE_GREEN);
+    }
+
+    @Test
+    void toWire_roundTrips() {
+        for (DeploymentStrategy s : DeploymentStrategy.values()) {
+            assertThat(DeploymentStrategy.fromWire(s.toWire())).isEqualTo(s);
+        }
+    }
+}