Reject blank metadata values

validate --entry values in write-metadata and return code 2 when the
value is blank to prevent invalid metadata writes.

also print stream and tag data in a stable structured format with
counts, indexed streams, and sorted tag keys for predictable output.

Author: TamKungZ

pom.xml

@@ -7,7 +7,7 @@
 
   <groupId>me.tamkungz.codecmedia</groupId>
   <artifactId>codecmedia-cli</artifactId>
-  <version>1.1.1</version>
+  <version>1.1.2</version>
   <packaging>jar</packaging>
 
   <name>CodecMedia CLI</name>

src/main/java/me/tamkungz/codecmedia/CodecMediaCli.java

@@ -412,6 +412,9 @@ private static int handleWriteMetadata(CodecMediaEngine engine, String[] args, P
             if (key.isBlank()) {
                 throw new IllegalArgumentException("Entry key must not be blank");
             }
+            if (value.isBlank()) {
+                throw new IllegalArgumentException("Entry value must not be blank");
+            }
             entries.put(key, value);
         }
 
@@ -439,8 +442,22 @@ private static void printProbe(PrintStream out, ProbeResult result) {
         out.println("extension=" + result.extension());
         out.println("mediaType=" + result.mediaType());
         out.println("durationMillis=" + result.durationMillis());
-        out.println("streams=" + result.streams());
-        out.println("tags=" + result.tags());
+
+        var streams = result.streams();
+        out.println("streams.count=" + streams.size());
+        for (int i = 0; i < streams.size(); i++) {
+            out.println("streams[" + i + "]=" + streams.get(i));
+        }
+
+        var tags = result.tags();
+        if (tags == null || tags.isEmpty()) {
+            out.println("tags.count=0");
+        } else {
+            out.println("tags.count=" + tags.size());
+            tags.entrySet().stream()
+                    .sorted(Map.Entry.comparingByKey())
+                    .forEach(entry -> out.println("tags." + entry.getKey() + "=" + entry.getValue()));
+        }
     }
 
     /**

src/test/java/me/tamkungz/codecmedia/CodecMediaCliTest.java

@@ -76,6 +76,14 @@ void shouldReturnCode2WhenWriteMetadataEntryValueMissing() {
         assertTrue(result.err().contains("Usage: write-metadata"));
     }
 
+    @Test
+    void shouldReturnCode2WhenWriteMetadataEntryValueBlank() {
+        RunResult result = runCli(new String[] {"write-metadata", "in.mp3", "--entry", "artist=   "});
+
+        assertEquals(2, result.code());
+        assertTrue(result.err().contains("Entry value must not be blank"));
+    }
+
     @Test
     void shouldReturnCode2WhenPlayHasUnknownOption() {
         RunResult result = runCli(new String[] {"play", "song.mp3", "--nope"});