feat: Support time travel for reading Lance dataset

[fightBoxing]

Summary

Implements time travel support for reading Lance datasets, addressing #5.

Changes

Configuration Options

• read.version (Integer): Specify a dataset version number to read a specific historical version
• read.timestamp (Long): Specify a timestamp in milliseconds to derive the dataset version (best-effort)

Implementation Details

• Updated LanceOptions with readVersion and readTimestamp fields, including validation
• Updated LanceSource.open() to use ReadOptions.Builder.setVersion() when a version is specified
• Updated LanceDynamicTableFactory to expose new config options for SQL DDL usage
• Updated LanceSource.Builder with version() and timestamp() methods

Usage Examples

DataStream API:

LanceSource source = LanceSource.builder()
    .path("/path/to/dataset")
    .version(3)  // Read version 3
    .build();

SQL DDL:

CREATE TABLE lance_table (
    id BIGINT,
    name STRING
) WITH (
    'connector' = 'lance',
    'path' = '/path/to/dataset',
    'read.version' = '3'
);

Testing

• Added 12 unit tests covering version/timestamp time travel, validation, and builder API

Closes #5