Add Polars and DuckDB quickstarts for the resource dataset

[ChaoYue0307]

Outcome

Add copy-pasteable Polars and DuckDB quickstarts to data/README.md so readers can query the resource dataset without first learning the project tooling.

Scope

• Show how to load the CSV or Parquet dataset with Polars.
• Show how to query the Parquet dataset directly with DuckDB.
• Include one useful example in each tool, such as filtering for whole-loop resources or a lifecycle stage.
• Keep both examples independent of the repository runtime and short enough to understand at a glance.
• Mention any package installation command required to run the snippets.

Acceptance criteria

• Both snippets run against the current files in data/.
• Their output and selected columns are explained in one sentence each.
• npx --yes markdownlint-cli2 **/*.md passes.
• No new project dependency is added.

Useful context

• Dataset guide: data/README.md
• Dataset schema: data/schema.json

Comment on this issue if you want the task assigned or need a sample expected result.