docs: add DOCKER_GUIDE.md and fix .env parsing; chore: update docker and script configurations

docker/init-scripts/02-optimization.sql

@@ -0,0 +1,43 @@
+-- Create a read-only user for API access (optional security)
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT FROM pg_roles WHERE rolname = 'btc_api') THEN
+        CREATE USER btc_api WITH PASSWORD 'api_password_change_me';
+    END IF;
+END
+$$;
+
+-- Grant read-only permissions
+GRANT CONNECT ON DATABASE btc_data TO btc_api;
+GRANT USAGE ON SCHEMA public TO btc_api;
+GRANT SELECT ON ALL TABLES IN SCHEMA public TO btc_api;
+
+-- Grant sequence access for ID columns
+GRANT USAGE ON ALL SEQUENCES IN SCHEMA public TO btc_api;
+
+-- Apply to future tables
+ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO btc_api;
+
+-- Create continuous aggregate for hourly stats (optional optimization)
+CREATE MATERIALIZED VIEW IF NOT EXISTS hourly_stats
+WITH (timescaledb.continuous) AS
+SELECT 
+    time_bucket('1 hour', time) as bucket,
+    symbol,
+    interval,
+    FIRST(open, time) as first_open,
+    MAX(high) as max_high,
+    MIN(low) as min_low,
+    LAST(close, time) as last_close,
+    SUM(volume) as total_volume,
+    COUNT(*) as candle_count
+FROM candles
+GROUP BY bucket, symbol, interval;
+
+-- Add refresh policy for continuous aggregate
+SELECT add_continuous_aggregate_policy('hourly_stats',
+    start_offset => INTERVAL '1 month',
+    end_offset => INTERVAL '1 hour',
+    schedule_interval => INTERVAL '1 hour',
+    if_not_exists => TRUE
+);