Feature/solutions accelerators and demos (#1100)

## Changes
* **New Industry Accelerators:** Added comprehensive Banking and Fashion
industry demos to the `demos/dqx_demo_industry/` directory.
* `dqx_banking_demo.py`: Focused on fraud detection and transaction
monitoring.
* `dqx_fashion_demo.py`: Rebuilt with industry best practices, including
custom check functions and 11 industry-specific quality rules.
* **Improved Repo Organization:** Moved the Manufacturing demo
(`dqx_manufacturing_demo.py`) into the `demos/dqx_demo_industry/`
subdirectory.
* **Enhanced Documentation:** Updated `docs/dqx/docs/demos.mdx` with a
new "Industry Accelerators" section

### Linked issues
Resolves #454

### Tests
- [x] manually tested
- [ ] added unit tests
- [ ] added integration tests
- [ ] added end-to-end tests
- [ ] added performance tests

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Co-authored-by: Marcin Wojtyczka <marcin.wojtyczka@databricks.com>

Author: fedeflowers