chore: import upstream snapshot with attribution

.env.example

@@ -0,0 +1,22 @@
+# OpenSquilla API Keys
+# Copy this file to .env and fill in your keys:
+#   cp .env.example .env
+
+# Required — LLM provider (OpenRouter)
+OPENROUTER_API_KEY=
+
+# Optional — TokenRhythm aggregator (DeepSeek/GLM/MiniMax/Kimi families)
+TOKENRHYTHM_API_KEY=
+
+# Optional — Brave Search API (auto-selected over DuckDuckGo when set)
+# Get a key at https://brave.com/search/api/
+BRAVE_SEARCH_API_KEY=
+
+# Optional — Web search network proxy.
+# Use this when Brave/DuckDuckGo endpoints are not reachable directly.
+# This affects web_search only; LLM provider proxy is configured separately.
+OPENSQUILLA_GATEWAY_SEARCH_PROXY=
+
+# Optional — allow web_search providers to use HTTP_PROXY/HTTPS_PROXY when no
+# explicit search proxy is set. Defaults to false for predictable behavior.
+OPENSQUILLA_GATEWAY_SEARCH_USE_ENV_PROXY=false