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/pygments/lexers/cplint.py

@@ -0,0 +1,43 @@
+"""
+    pygments.lexers.cplint
+    ~~~~~~~~~~~~~~~~~~~~~~
+
+    Lexer for the cplint language
+
+    :copyright: Copyright 2006-present by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.lexer import bygroups, inherit, words
+from pygments.lexers import PrologLexer
+from pygments.token import Operator, Keyword, Name, String, Punctuation
+
+__all__ = ['CplintLexer']
+
+
+class CplintLexer(PrologLexer):
+    """
+    Lexer for cplint files, including CP-logic, Logic Programs with Annotated
+    Disjunctions, Distributional Clauses syntax, ProbLog, DTProbLog.
+    """
+    name = 'cplint'
+    url = 'https://cplint.eu'
+    aliases = ['cplint']
+    filenames = ['*.ecl', '*.prolog', '*.pro', '*.pl', '*.P', '*.lpad', '*.cpl']
+    mimetypes = ['text/x-cplint']
+    version_added = '2.12'
+
+    tokens = {
+        'root': [
+            (r'map_query', Keyword),
+            (words(('gaussian', 'uniform_dens', 'dirichlet', 'gamma', 'beta',
+                    'poisson', 'binomial', 'geometric', 'exponential', 'pascal',
+                    'multinomial', 'user', 'val', 'uniform', 'discrete',
+                    'finite')), Name.Builtin),
+            # annotations of atoms
+            (r'([a-z]+)(:)', bygroups(String.Atom, Punctuation)),
+            (r':(-|=)|::?|~=?|=>', Operator),
+            (r'\?', Name.Builtin),
+            inherit,
+        ],
+    }