Expose channel history through the Java server SDK

This adds a thin getChannelHistory helper over the existing\nsigned get() surface so durable channel history queries match the\nrest of the phase-2 server SDK contract.

Constraint: Must preserve the existing SDK style and thin request shape where appropriate
Rejected: Leave history/recovery access as manual path construction only | inconsistent public surface
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Keep payload names aligned exactly with server event and query contracts
Tested: ./gradlew test
Not-tested: none

Author: countradooku

README.md

@@ -273,6 +273,20 @@ This library supports end-to-end encryption of private channels. Only you and yo
 
 **Note:** A single `trigger` call cannot target both encrypted and unencrypted channels simultaneously.
 
+### Channel history
+
+```java
+Map<String, String> params = new HashMap<>();
+params.put("limit", "50");
+params.put("direction", "newest_first");
+
+Result page = sockudo.getChannelHistory("my-channel", params);
+Result nextPage = sockudo.getChannelHistory(
+    "my-channel",
+    Collections.singletonMap("cursor", "opaque-cursor-from-previous-page")
+);
+```
+
 ## License
 
 This code is free to use under the terms of the MIT license.

src/main/java/io/sockudo/rest/SockudoAbstract.java

@@ -512,6 +512,30 @@ public T get(final String path, final Map<String, String> parameters) {
         return doGet(uri);
     }
 
+    /**
+     * Fetch durable history for a specific channel.
+     *
+     * @param channelName the channel to query
+     * @param parameters history query parameters such as limit, direction, cursor,
+     *                   start_serial, end_serial, start_time_ms, end_time_ms
+     * @return a {@link Result} object encapsulating the success state and response
+     */
+    public T getChannelHistory(final String channelName, final Map<String, String> parameters) {
+        Prerequisites.nonEmpty("channelName", channelName);
+        Prerequisites.isValidChannel(channelName);
+        return get("/channels/" + channelName + "/history", parameters);
+    }
+
+    /**
+     * Fetch durable history for a specific channel without additional query parameters.
+     *
+     * @param channelName the channel to query
+     * @return a {@link Result} object encapsulating the success state and response
+     */
+    public T getChannelHistory(final String channelName) {
+        return getChannelHistory(channelName, Collections.<String, String>emptyMap());
+    }
+
     protected abstract T doGet(final URI uri);
 
     /**

src/test/java/io/sockudo/rest/SockudoTest.java

@@ -241,6 +241,24 @@ public void reservedParameter() {
         });
     }
 
+    @Test
+    public void getChannelHistory() throws Exception {
+        context.checking(new Expectations() {{
+            oneOf(httpClient).execute(with(path("/apps/" + APP_ID + "/channels/history-room/history")));
+        }});
+
+        p.getChannelHistory("history-room");
+    }
+
+    @Test
+    public void getChannelHistoryWithParams() throws Exception {
+        context.checking(new Expectations() {{
+            oneOf(httpClient).execute(with(path("/apps/" + APP_ID + "/channels/history-room/history")));
+        }});
+
+        p.getChannelHistory("history-room", Collections.singletonMap("direction", "newest_first"));
+    }
+
     @Test
     public void testTriggerOnEncryptedChannel() throws IOException {
         final Sockudo pe = new Sockudo(APP_ID, KEY, SECRET, VALID_MASTER_KEY);