* feat: add processor plugin support
Add PluginType.PROCESSOR to the plugin system, enabling third-party
processor plugins via entry points. Includes a demo plugin package
with RegexFilterProcessor (process_before_batch) and
SemanticDedupProcessor (process_after_generation).
- Add PluginType.PROCESSOR with processor_type discriminator
- Create processor_types.py for ProcessorConfigT with plugin injection
- Register plugin processors in engine ProcessorRegistry
- Use RLock in PluginRegistry to prevent deadlocks during discovery
- Add demo package: data-designer-demo-processors
- Update processor and plugin documentation
* test: add processor plugin registration test
Verify that processor plugins from PluginRegistry are picked up
by create_default_processor_registry and registered correctly.
* test: simplify processor plugin registration test
* move ProcessorConfig to base and convert demo to e2e test
- Move ProcessorConfig from processors.py to config.base to guard
against circular deps (alongside SingleColumnConfig)
- Delete demo/ directory with regex_filter and semantic_dedup plugins
- Add regex_filter as an e2e processor plugin test in tests_e2e/
* move plan to plans/299/
* docs: restructure plugin docs with multi-file layout and seed reader type
- Update plugin overview to document both column generator and seed
reader plugin types
- Restructure example plugin to use separate config.py, impl.py, and
plugin.py files instead of a single-file approach
- Add sections for plugin validation and multiple plugins per package
- Document required config class methods (get_column_emoji,
required_columns, side_effect_columns)
* docs: clarify benefits of multi-file plugin structure
Expand explanation to mention circular dependency prevention
as a key reason for separating config, impl, and plugin modules.
* docs: fix import ordering in plugin example
* import spacing
* better example column name
* add a bit to the comment
* Updated plugin docs
* update plugin overview call-to-action wording
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Co-authored-by: Kirit93 <kthadaka@nvidia.com>
