fix: add socksio dependency to support SOCKS proxy (#961)

When users have a SOCKS proxy configured (via HTTP_PROXY or ALL_PROXY
environment variables), httpx's AsyncClient automatically tries to use
it but fails without the socksio package installed.

Changed httpx dependency from httpx>=0.25.0 to httpx[socks]>=0.25.0 to
include the socksio package as an extra dependency.

Fixes #961

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

Author: 3 people

backend/pyproject.toml

@@ -6,7 +6,7 @@ requires-python = ">=3.13"
 dependencies = [
     "fastapi>=0.109.0",
     "uvicorn>=0.27.0",
-    "httpx>=0.25.0",
+    "httpx[socks]>=0.25.0",
     "httpx-socks>=0.9.0",
     "beautifulsoup4>=4.12.0",
     "sqlmodel>=0.0.14",