Initial commit — Cortex API + Inara identity

Cortex: FastAPI backend serving Inara via Claude/Gemini CLI backends.
Includes SSE streaming chat, session persistence, Google Chat webhook
handler, and Docker support.

Inara: Identity files (persona, soul, protocols, memory, context tiers)
mounted read-only into the container at runtime.

Features in initial cut:
- /chat endpoint with SSE keepalive + LLM fallback
- Session store with rolling history window
- Markdown rendering, copy-to-clipboard, links open in new tab
- Stacked right-column input controls (height selector, enter toggle,
  note mode with public/private) — semi-hidden until textarea grows
- /note endpoint for injecting public context into session history
- Docker Compose config (local dev runs natively; Docker for server)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cortex/.env.example

@@ -0,0 +1,33 @@
+# Auth is handled by the claude CLI (claude setup-token) — no API key needed here.
+# ANTHROPIC_API_KEY=only_needed_if_switching_to_sdk
+
+# Path to the inara/ identity directory — relative to cortex/ or absolute
+INARA_DIR=../inara
+
+# Path for persistent JSON session files
+SESSIONS_DIR=./data/sessions
+
+# LLM defaults
+DEFAULT_MODEL=claude-sonnet-4-6
+DEFAULT_TIER=2
+
+# Session rolling window — number of messages to keep (user + assistant pairs)
+# 40 = 20 turns
+MAX_HISTORY_MESSAGES=40
+
+# Per-backend timeouts (seconds)
+# Gemini is generous — it frequently takes 30-60s under load
+# Local models may need time to load into VRAM before first response
+TIMEOUT_CLAUDE=60
+TIMEOUT_GEMINI=120
+TIMEOUT_LOCAL=300
+
+# Google Chat — must respond within 30s or Chat shows an error to the user
+GOOGLE_CHAT_TIMEOUT=25
+# Backend pinned for Google Chat (claude recommended — more reliable within 25s)
+GOOGLE_CHAT_BACKEND=claude
+# TODO: add GOOGLE_CHAT_TOKEN for request verification once endpoint is public
+
+# Server
+PORT=8000
+HOST=0.0.0.0