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/click/_textwrap.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+import collections.abc as cabc
+import textwrap
+from contextlib import contextmanager
+
+
+class TextWrapper(textwrap.TextWrapper):
+    def _handle_long_word(
+        self,
+        reversed_chunks: list[str],
+        cur_line: list[str],
+        cur_len: int,
+        width: int,
+    ) -> None:
+        space_left = max(width - cur_len, 1)
+
+        if self.break_long_words:
+            last = reversed_chunks[-1]
+            cut = last[:space_left]
+            res = last[space_left:]
+            cur_line.append(cut)
+            reversed_chunks[-1] = res
+        elif not cur_line:
+            cur_line.append(reversed_chunks.pop())
+
+    @contextmanager
+    def extra_indent(self, indent: str) -> cabc.Iterator[None]:
+        old_initial_indent = self.initial_indent
+        old_subsequent_indent = self.subsequent_indent
+        self.initial_indent += indent
+        self.subsequent_indent += indent
+
+        try:
+            yield
+        finally:
+            self.initial_indent = old_initial_indent
+            self.subsequent_indent = old_subsequent_indent
+
+    def indent_only(self, text: str) -> str:
+        rv = []
+
+        for idx, line in enumerate(text.splitlines()):
+            indent = self.initial_indent
+
+            if idx > 0:
+                indent = self.subsequent_indent
+
+            rv.append(f"{indent}{line}")
+
+        return "\n".join(rv)