Add Polaris Sync tool to polaris-tools

[mansehajsingh]

Builds on top of #1.

Adds an in development tool in the polaris-synchronizer/ directory to migrate between two Polaris instances.

• Changed file headers
• Ported over code
• Built tool to conform to the build system introduced in Initial commit for Iceberg catalog migrator #1

Roadmap: The tool is in development and there are a multitude of enhancements planned to generalize the tool across a wider array of use cases. Before these enhancements are carried out, it is important that the tool becomes generally available to the community so the wider Polaris group can pitch in ideas and contributions to guide the tool to align with new features we plan to introduce in Polaris's roadmap. Some planned enhancements include:

• Generalize tool auth flow to be less dependent on the deprecated client credentials flow for the catalog and add token refresh for long running jobs
• Improve robustness with enhancements like retries w/ exponential backoff, timeouts, etc.
• Determine how Policy migration might look once the Policy APIs are complete in Polaris.

[mansehajsingh]

I have opened ajantha-bhat#1 to get a more accurate look at what the tool adds until #1 goes into main.