feat(phase1): add image storage utilities

- Create backend/services/image_storage.py with 4 core functions:
  - sanitize_filename(): remove unsafe chars, limit to 255 chars, convert to lowercase
  - get_unique_filename(): handle collisions with UUID suffix (format: {name}_{uuid8}_{variant}.jpg)
  - ensure_image_directories(): create /images/ root and category subdirs on startup
  - save_image(): save bytes to /images/{category}/{filename}, returns relative path
- Create comprehensive test suite (22 tests) covering all functionality
- Integrate ensure_image_directories() into FastAPI startup event
- Directory structure: /images/{category}/{filename}
- Collision handling: auto-suffix with UUID if filename exists
- All tests passing, pathlib.Path for safe operations

venv/lib/python3.12/site-packages/tenacity-9.1.4.dist-info/METADATA

@@ -0,0 +1,31 @@
+Metadata-Version: 2.4
+Name: tenacity
+Version: 9.1.4
+Summary: Retry code until it succeeds
+Home-page: https://github.com/jd/tenacity
+Author: Julien Danjou
+Author-email: julien@danjou.info
+License: Apache 2.0
+Classifier: Intended Audience :: Developers
+Classifier: License :: OSI Approved :: Apache Software License
+Classifier: Programming Language :: Python
+Classifier: Programming Language :: Python :: 3
+Classifier: Programming Language :: Python :: 3 :: Only
+Classifier: Programming Language :: Python :: 3.10
+Classifier: Programming Language :: Python :: 3.11
+Classifier: Programming Language :: Python :: 3.12
+Classifier: Programming Language :: Python :: 3.13
+Classifier: Programming Language :: Python :: 3.14
+Classifier: Topic :: Utilities
+Requires-Python: >=3.10
+License-File: LICENSE
+Provides-Extra: doc
+Requires-Dist: reno; extra == "doc"
+Requires-Dist: sphinx; extra == "doc"
+Provides-Extra: test
+Requires-Dist: pytest; extra == "test"
+Requires-Dist: tornado>=4.5; extra == "test"
+Requires-Dist: typeguard; extra == "test"
+Dynamic: license-file
+
+Tenacity is a general-purpose retrying library to simplify the task of adding retry behavior to just about anything.