README: consistent structure, cross-language examples, policy file

Author: lgutschow

README.md

@@ -8,7 +8,7 @@ Data protection SDK for Java — format-preserving encryption (FF1/FF3), AES-GCM
 <dependency>
     <groupId>io.cyphera</groupId>
     <artifactId>cyphera</artifactId>
-    <version>0.0.1-alpha.1</version>
+    <version>0.0.1-alpha.2</version>
 </dependency>
 ```
 
@@ -18,39 +18,49 @@ Available on [Maven Central](https://central.sonatype.com/artifact/io.cyphera/cy
 
 ```java
 import io.cyphera.Cyphera;
-import java.util.HashMap;
-import java.util.Map;
 
-Map<String, Object> config = new HashMap<>();
+// Auto-discover: checks CYPHERA_POLICY_FILE env, ./cyphera.json, /etc/cyphera/cyphera.json
+Cyphera c = Cyphera.load();
 
-Map<String, Object> policies = new HashMap<>();
-Map<String, Object> ssn = new HashMap<>();
-ssn.put("engine", "ff1");
-ssn.put("key_ref", "my-key");
-ssn.put("tag", "T01");
-policies.put("ssn", ssn);
-config.put("policies", policies);
-
-Map<String, Object> keys = new HashMap<>();
-Map<String, Object> key = new HashMap<>();
-key.put("material", "2B7E151628AED2A6ABF7158809CF4F3C");
-keys.put("my-key", key);
-config.put("keys", keys);
-
-Cyphera c = Cyphera.fromMap(config);
+// Or load from a specific file
+Cyphera c = Cyphera.fromFile("./config/cyphera.json");
 
 // Protect
 String encrypted = c.protect("123-45-6789", "ssn");
-// → "T01k7R-m2-9xPq" (tagged, dashes preserved)
+// → "T01i6J-xF-07pX" (tagged, dashes preserved)
 
 // Access (tag-based, no policy name needed)
 String decrypted = c.access(encrypted);
 // → "123-45-6789"
 ```
 
+## Policy File (cyphera.json)
+
+```json
+{
+  "policies": {
+    "ssn": { "engine": "ff1", "key_ref": "my-key", "tag": "T01" }
+  },
+  "keys": {
+    "my-key": { "material": "2B7E151628AED2A6ABF7158809CF4F3C" }
+  }
+}
+```
+
+## Cross-Language Compatible
+
+Java, Rust, and Node produce identical output for the same inputs:
+
+```
+Input:       123-45-6789
+Java:        T01i6J-xF-07pX
+Rust:        T01i6J-xF-07pX
+Node:        T01i6J-xF-07pX
+```
+
 ## Status
 
-Alpha. API is unstable. Cross-language test vectors validated against Rust implementation.
+Alpha. API is unstable. Cross-language test vectors validated against Rust and Node implementations.
 
 ## License