perf(ci): compile once with PVC sccache, package with Kaniko

Split the build pipeline: one compile-services job builds all 8 service
binaries with PVC-backed sccache, saves as artifacts. Then 9 Kaniko jobs
just package pre-built binaries into slim runtime images (~30s each).

Before: 9 parallel Kaniko jobs each doing full cargo build --release
  (~20min each, no sccache, 9x duplicated dep compilation)
After:  1 compile job with sccache (~5min cached) + 9 package jobs (~30s)

- Add compile stage between test and build
- Add Dockerfile.runtime (minimal debian + pre-built binary)
- Add Dockerfile.web-gateway-runtime (Node dashboard + pre-built binary)
- Keep Dockerfile.training via Kaniko (needs CUDA dev image for H100)
- Remove all SCCACHE_BUCKET build-args from service builds
- Use dir:// context for Kaniko (only sends build-out/ dir, not full repo)

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

scripts/init-db-dev.sql

@@ -0,0 +1,22 @@
+-- Development Database Initialization Script
+-- This script creates a minimal database structure for development
+
+-- Create the foxhunt database
+CREATE DATABASE foxhunt;
+
+-- Connect to the database
+\c foxhunt;
+
+-- Create extensions
+CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
+CREATE EXTENSION IF NOT EXISTS "btree_gin";
+
+-- Include the existing init-db.sql content
+\i init-db.sql
+
+-- Apply all migrations in order
+\i migrations/001_up_create_core_tables.sql
+\i migrations/002_up_create_risk_performance_tables.sql
+\i migrations/007_configuration_schema.sql
+\i migrations/011_create_market_data_tables.sql
+\i migrations/012_create_event_and_config_tables.sql