[AMORO-4128] Drop mixed Flink 1.16 support (#4132)

* Drop mixed Flink 1.16 support (#4128)

Remove mixed Flink 1.16 modules and update documentation to reflect
the supported Flink versions (1.17, 1.18). This unblocks future
Iceberg upgrades that no longer support Flink 1.16.

- Remove v1.16/amoro-mixed-flink-1.16 and v1.16/amoro-mixed-flink-runtime-1.16 modules
- Remove Flink 1.16 entries from parent pom.xml module list
- Update version matrices in README and docs
- Update Flink documentation links from 1.16 to 1.17
- Clean up stale Flink 1.15 references in docs

Signed-off-by: Jiwon Park <jpark92@outlook.kr>

* Address review comment: sync MixedCatalog method with Iceberg 1.6.x source

Signed-off-by: Jiwon Park <jpark92@outlook.kr>

* Fix stale Spark 3.2 path reference in deployment docs

Update the example path from the non-existent
amoro-format-mixed-spark/v3.2 to amoro-mixed-spark/v3.3 to match
the current project structure. Also remove a trailing parenthesis
typo in the jar filename comment.

Signed-off-by: Jiwon Park <jpark92@outlook.kr>

---------

Signed-off-by: Jiwon Park <jpark92@outlook.kr>

Author: j1wonpark

README.md

@@ -82,7 +82,7 @@ Amoro support multiple processing engines for Mixed format as below:
 
 | Processing Engine | Version                | Batch Read  | Batch Write | Batch Overwrite | Streaming Read | Streaming Write | Create Table | Alter Table |
 |-------------------|------------------------|-------------|-------------|-----------------|----------------|-----------------|--------------|-------------|
-| Flink             | 1.16.x, 1.17.x, 1.18.x |  ✔   |   ✔   |       ✖   |      ✔   |       ✔   |    ✔   |   ✖   |
+| Flink             | 1.17.x, 1.18.x         |  ✔   |   ✔   |       ✖   |      ✔   |       ✔   |    ✔   |   ✖   |
 | Spark             | 3.3, 3.4, 3.5          |  ✔   |   ✔   |       ✔   |      ✖   |       ✖   |    ✔   |   ✔   |
 | Hive              | 2.x, 3.x               |  ✔  |   ✖  |       ✔  |      ✖  |       ✖  |    ✖  |   ✔  |
 | Trino             | 406                    |  ✔  |   ✖  |       ✔  |      ✖  |       ✖  |    ✖  |   ✔  |

amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/catalog/MixedCatalog.java

@@ -665,7 +665,7 @@ private void validateColumnOrder(CatalogBaseTable table) {
 
   /**
    * copy from
-   * https://github.com/apache/iceberg/blob/main/flink/v1.16/flink/src/main/java/org/apache/iceberg/flink/FlinkCatalog.java#L425C23-L425C54
+   * https://github.com/apache/iceberg/blob/1.6.x/flink/v1.17/flink/src/main/java/org/apache/iceberg/flink/FlinkCatalog.java#L425-L448
    *
    * @param ct1 CatalogTable before
    * @param ct2 CatalogTable after
@@ -687,9 +687,15 @@ private static void validateTableSchemaAndPartition(CatalogTable ct1, CatalogTab
     if (!(Objects.equal(ts1.getTableColumns(), ts2.getTableColumns())
         && Objects.equal(ts1.getWatermarkSpecs(), ts2.getWatermarkSpecs())
         && equalsPrimary)) {
-      throw new UnsupportedOperationException("Altering schema is not supported yet.");
+      throw new UnsupportedOperationException(
+          "Altering schema is not supported in the old alterTable API. "
+              + "To alter schema, use the other alterTable API and provide a list of TableChange's.");
     }
 
+    validateTablePartition(ct1, ct2);
+  }
+
+  private static void validateTablePartition(CatalogTable ct1, CatalogTable ct2) {
     if (!ct1.getPartitionKeys().equals(ct2.getPartitionKeys())) {
       throw new UnsupportedOperationException("Altering partition keys is not supported yet.");
     }

amoro-format-mixed/amoro-mixed-flink/pom.xml

@@ -36,8 +36,6 @@
         <module>amoro-mixed-flink-common</module>
         <module>amoro-mixed-flink-common-format</module>
         <module>amoro-mixed-flink-common-iceberg-bridge</module>
-        <module>v1.16/amoro-mixed-flink-1.16</module>
-        <module>v1.16/amoro-mixed-flink-runtime-1.16</module>
         <module>v1.17/amoro-mixed-flink-1.17</module>
         <module>v1.17/amoro-mixed-flink-runtime-1.17</module>
         <module>v1.18/amoro-mixed-flink-1.18</module>