feat: Add URL representation for storage paths and remove orphaned docs (#1328)

* feat: Add consistent URL representation for all storage paths (#1326)

Implements unified URL handling for all storage backends including local files:

- Add URL_PROTOCOLS tuple including file://
- Add is_url() to check if path is a URL
- Add normalize_to_url() to convert local paths to file:// URLs
- Add parse_url() to parse any URL into protocol and path
- Add StorageBackend.get_url() to return full URLs for any backend
- Add comprehensive unit tests for URL functions

This enables consistent internal representation across all storage types,
aligning with fsspec's unified approach to filesystems.

Closes #1326

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* test: Remove redundant URL tests from test_object.py

The TestRemoteURLSupport class tested is_remote_url and parse_remote_url
which were renamed to is_url and parse_url. These tests are now redundant
as comprehensive coverage exists in tests/unit/test_storage_urls.py.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix: Remove trailing whitespace from blank line in json.ipynb

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* style: Apply ruff formatting

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* chore: Remove accidentally committed local config files

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* style: Apply ruff formatting to test files

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* docs: Remove orphaned archive documentation

Content has been migrated to datajoint-docs repository.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

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Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: dimitri-yatsenko