### What?
Fixes the `custom.plugin-import-export.disabled` flag to correctly
disable fields in all nested structures including:
- Groups
- Arrays
- Tabs
- Blocks
Previously, only top-level fields or direct children were respected.
This update ensures nested paths (e.g. `group.array.field1`,
`blocks.hero.title`, etc.) are matched and filtered from exports.
### Why?
- Updated regex logic in both `createExport` and Preview components to
recursively support:
- Indexed array fields (e.g. `array_0_field1`)
- Block fields with slugs (e.g. `blocks_0_hero_title`)
- Nested field accessors with correct part-by-part expansion
### How?
To allow users to disable entire field groups or deeply nested fields in
structured layouts.