feat(dapr): add environment variable substitution to components

- Update Dapr components to use \ syntax:
  * statestore/redis.yaml: REDIS_HOST, REDIS_PASSWORD
  * statestore/postgres.yaml: POSTGRES_CONNECTION_STRING
  * pubsub/redis.yaml: REDIS_HOST, REDIS_PASSWORD

- Create comprehensive .env.example file with:
  * OpenAI configuration (API key - required)
  * Dapr configuration (ports, endpoints, state store)
  * Redis configuration (host, password)
  * PostgreSQL configuration (credentials, connection string)
  * Development environment (cache directories)
  * GPU configuration notes

- All variables documented with descriptions and defaults
- Consistent with docker-compose.yml environment configuration

MEDIUM PRIORITY openai#5: COMPLETED - Environment variable consistency

Author: DeanLuus22021994

.devcontainer/.env.example

@@ -0,0 +1,93 @@
+# DevContainer Environment Variables
+# Copy this file to .env and customize as needed
+
+# =============================================================================
+# OpenAI Configuration
+# =============================================================================
+# Required: Your OpenAI API key for authentication
+OPENAI_API_KEY=your-api-key-here
+
+# =============================================================================
+# Dapr Configuration
+# =============================================================================
+# Dapr gRPC port (default: 50001)
+DAPR_GRPC_PORT=50001
+
+# Dapr HTTP port (default: 3500)
+DAPR_HTTP_PORT=3500
+
+# Default Dapr state store component name (default: statestore)
+DAPR_STATE_STORE=statestore
+
+# Dapr HTTP endpoint for bindings (default: http://dapr-sidecar:3500)
+DAPR_HTTP_ENDPOINT=http://dapr-sidecar:3500
+
+# =============================================================================
+# Redis Configuration
+# =============================================================================
+# Redis host and port (default: redis:6379)
+REDIS_HOST=redis:6379
+
+# Redis password (default: empty for no authentication)
+REDIS_PASSWORD=
+
+# =============================================================================
+# PostgreSQL Configuration
+# =============================================================================
+# PostgreSQL username (default: postgres)
+POSTGRES_USER=postgres
+
+# PostgreSQL password (default: postgres)
+POSTGRES_PASSWORD=postgres
+
+# PostgreSQL database name (default: dapr)
+POSTGRES_DB=dapr
+
+# PostgreSQL host (default: postgres)
+POSTGRES_HOST=postgres
+
+# PostgreSQL port (default: 5432)
+POSTGRES_PORT=5432
+
+# PostgreSQL connection string (auto-generated if not provided)
+# Format: host=HOST user=USER password=PASSWORD dbname=DB port=PORT
+POSTGRES_CONNECTION_STRING=host=postgres user=postgres password=postgres dbname=dapr port=5432
+
+# =============================================================================
+# Development Environment
+# =============================================================================
+# Node.js module path for development tools
+NODE_PATH=/opt/node_modules
+
+# npm configuration prefix
+npm_config_prefix=/opt/node_modules
+
+# Python cache directory
+PYTHONPYCACHEPREFIX=/opt/python-cache/__pycache__
+
+# Pytest cache directory
+PYTEST_CACHE_DIR=/opt/pytest-cache
+
+# Mypy cache directory
+MYPY_CACHE_DIR=/opt/mypy-cache
+
+# Ruff cache directory
+RUFF_CACHE_DIR=/opt/ruff-cache
+
+# =============================================================================
+# GPU Configuration (Optional)
+# =============================================================================
+# GPU support is automatically configured if NVIDIA GPU and drivers are available
+# No manual configuration needed - Docker will detect and use available GPUs
+# To disable GPU support, comment out the deploy.resources.reservations section
+# in docker-compose.yml for app-dev and app-prod services
+
+# =============================================================================
+# Notes
+# =============================================================================
+# - All variables have sensible defaults for local development
+# - Only OPENAI_API_KEY is strictly required
+# - Variables with ${VAR:-default} syntax in docker-compose.yml will use
+#   values from this file if set, otherwise use the default
+# - Dapr components support environment variable substitution
+# - Cache directories are mounted as volumes for performance

.devcontainer/dapr-components/pubsub/redis.yaml

@@ -7,6 +7,6 @@ spec:
   version: v1
   metadata:
     - name: redisHost
-      value: redis:6379
+      value: "${REDIS_HOST:-redis:6379}"
     - name: redisPassword
-      value: ""
+      value: "${REDIS_PASSWORD:-}"

.devcontainer/dapr-components/statestore/postgres.yaml

@@ -7,4 +7,4 @@ spec:
   version: v2
   metadata:
     - name: connectionString
-      value: "host=postgres user=postgres password=postgres dbname=dapr port=5432"
+      value: "${POSTGRES_CONNECTION_STRING:-host=postgres user=postgres password=postgres dbname=dapr port=5432}"

.devcontainer/dapr-components/statestore/redis.yaml

@@ -7,8 +7,8 @@ spec:
   version: v1
   metadata:
     - name: redisHost
-      value: redis:6379
+      value: "${REDIS_HOST:-redis:6379}"
     - name: redisPassword
-      value: ""
+      value: "${REDIS_PASSWORD:-}"
     - name: actorStateStore
       value: "false"