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/bare.py

@@ -0,0 +1,101 @@
+"""
+    pygments.lexers.bare
+    ~~~~~~~~~~~~~~~~~~~~
+
+    Lexer for the BARE schema.
+
+    :copyright: Copyright 2006-present by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.lexer import RegexLexer, words, bygroups
+from pygments.token import Text, Comment, Keyword, Name, Literal, Whitespace
+
+__all__ = ['BareLexer']
+
+
+class BareLexer(RegexLexer):
+    """
+    For BARE schema source.
+    """
+    name = 'BARE'
+    url = 'https://baremessages.org'
+    filenames = ['*.bare']
+    aliases = ['bare']
+    version_added = '2.7'
+
+    keywords = [
+        'type',
+        'enum',
+        'u8',
+        'u16',
+        'u32',
+        'u64',
+        'uint',
+        'i8',
+        'i16',
+        'i32',
+        'i64',
+        'int',
+        'f32',
+        'f64',
+        'bool',
+        'void',
+        'data',
+        'string',
+        'optional',
+        'map',
+    ]
+
+    tokens = {
+        'root': [
+            (r'(type)(\s+)([A-Z][a-zA-Z0-9]+)(\s+)(\{)',
+             bygroups(Keyword, Whitespace, Name.Class, Whitespace, Text), 'struct'),
+            (r'(type)(\s+)([A-Z][a-zA-Z0-9]+)(\s+)(\()',
+             bygroups(Keyword, Whitespace, Name.Class, Whitespace, Text), 'union'),
+            (r'(type)(\s+)([A-Z][a-zA-Z0-9]+)(\s+)',
+             bygroups(Keyword, Whitespace, Name, Whitespace), 'typedef'),
+            (r'(enum)(\s+)([A-Z][a-zA-Z0-9]+)(\s+\{)',
+             bygroups(Keyword, Whitespace, Name.Class, Whitespace), 'enum'),
+            (r'#.*?$', Comment),
+            (r'\s+', Whitespace),
+        ],
+        'struct': [
+            (r'\{', Text, '#push'),
+            (r'\}', Text, '#pop'),
+            (r'([a-zA-Z0-9]+)(:)(\s*)',
+             bygroups(Name.Attribute, Text, Whitespace), 'typedef'),
+            (r'\s+', Whitespace),
+        ],
+        'union': [
+            (r'\)', Text, '#pop'),
+            (r'(\s*)(\|)(\s*)', bygroups(Whitespace, Text, Whitespace)),
+            (r'[A-Z][a-zA-Z0-9]+', Name.Class),
+            (words(keywords), Keyword),
+            (r'\s+', Whitespace),
+        ],
+        'typedef': [
+            (r'\[\]', Text),
+            (r'#.*?$', Comment, '#pop'),
+            (r'(\[)(\d+)(\])', bygroups(Text, Literal, Text)),
+            (r'<|>', Text),
+            (r'\(', Text, 'union'),
+            (r'(\[)([a-z][a-z-A-Z0-9]+)(\])', bygroups(Text, Keyword, Text)),
+            (r'(\[)([A-Z][a-z-A-Z0-9]+)(\])', bygroups(Text, Name.Class, Text)),
+            (r'([A-Z][a-z-A-Z0-9]+)', Name.Class),
+            (words(keywords), Keyword),
+            (r'\n', Text, '#pop'),
+            (r'\{', Text, 'struct'),
+            (r'\s+', Whitespace),
+            (r'\d+', Literal),
+        ],
+        'enum': [
+            (r'\{', Text, '#push'),
+            (r'\}', Text, '#pop'),
+            (r'([A-Z][A-Z0-9_]*)(\s*=\s*)(\d+)',
+             bygroups(Name.Attribute, Text, Literal)),
+            (r'([A-Z][A-Z0-9_]*)', bygroups(Name.Attribute)),
+            (r'#.*?$', Comment),
+            (r'\s+', Whitespace),
+        ],
+    }