[Feature] Introduce Merge Engines for Primary-Key Table

### Search before asking

- [X] I searched in the [issues](https://github.com/alibaba/fluss/issues) and found nothing similar.

### Motivation

We propose the introduction of merge engines for primary-key tables, enhancing data management and query capabilities. This feature will encompass the following merge engines, each with distinct functionalities:

- Version-Based Merge: This merge engine will allow data consolidation based on version numbers. It is very similar to ClickHouse [ReplacingMergeTree](https://clickhouse.com/docs/en/guides/replacing-merge-tree) that keeps the row with the highest version number. This is also very similar to HBase [checkAndPut](https://hbase.apache.org/1.2/apidocs/org/apache/hadoop/hbase/client/Table.html#checkAndPut(byte[],%20byte[],%20byte[],%20byte[],%20org.apache.hadoop.hbase.client.Put)) that updates records only when the condition is true. In this way, the out-of-order data can be guaranteed to be ultimately consistent with the upstream.

- First-Row Based Merge: Designed to retain the first occurrence of a row with the same primary key, this engine boosts performance by minimizing writes to the kv store and generates only insert-only changelogs (some downstream jobs only accept insert-only changelogs).

- Aggregate Based Merge: This engine will facilitate the merging of data by aggregating records, which is particularly useful for summarizing information and analytics purposes. It will support operations like `sum`, `max`, `min`, `count`, `avg`, among others, providing robust analytic capabilities.

### Solution

Introduce table properties (configured via Flink DDL with options):
```properties
'table.merge-engine' = 'first_row|version|aggregate'
'table.merge-engine.version.column' = ''
'table.merge-engine.aggregate.' = 'sum | max | min | count | avg | first_value | last_value'
```

The `merge-engine` properties are table storage properties, and therefore can't be changed after table creation.

## How to Use

### Version-Based Merge

```sql
CREATE TABLE fluss_table (
id BIGINT,
ts BIGINT,
data STRING,
PRIMARY KEY (id) NOT ENFORCED
) WITH (
'connector' = 'fluss',
'bootstrap.address' = '...',
'table.merge-engine' = 'version',
'table.merge-engine.version.column' = 'ts' -- updates when new ts >= old ts
);
```

### First-Row-Based Merge

```sql
CREATE TABLE fluss_table (
id BIGINT,
version BIGINT,
data STRING,
PRIMARY KEY (id) NOT ENFORCED
) WITH (
'connector' = 'fluss',
'bootstrap.address' = '...',
'table.merge-engine' = 'first_row' -- only the first row of the primary key will be retained.
);
```

### Aggregate-Based Merge

```sql
CREATE TABLE fluss_table (
id BIGINT,
price DOUBLE,
sales BIGINT,
PRIMARY KEY (id) NOT ENFORCED
) WITH (
'connector' = 'fluss',
'bootstrap.address' = '...',
'table.merge-engine' = 'aggregate',
'table.merge-engine.aggregate.price' = 'max',
'table.merge-engine.aggregate.sales' = 'sum'
);
```

### Anything else?

Subtasks:

- [x] #133
- [x] #213
- [ ] #2133

### Willingness to contribute

- [ ] I'm willing to submit a PR!

The issue describes merge-engine table properties configured through Flink DDL, with version, first-row, and aggregate examples, but names no source files, tests, or implementation entry points. Start by locating the primary-key table storage and table-property handling; done would require the proposed engines, configuration validation, and coverage for the documented behaviors.

Written by the indexing model from the issue text.