chore: reorganize repository structure

- Move docker-compose files to .docker/compose/
- Move docker-entrypoint.sh to .docker/
- Move DOCKER.md to .docker/README.md
- Move 16 implementation docs to docs/implementation/
- Delete test artifacts (block_test.txt, caddy_*.json)
- Update all references in Dockerfile, Makefile, tasks, scripts
- Add .github/instructions/structure.instructions.md for enforcement
- Update CHANGELOG.md

Root level reduced from 81 items to ~35 visible items.

.docker/compose/docker-compose.local.yml

@@ -0,0 +1,57 @@
+services:
+  charon:
+    image: charon:local
+    container_name: charon
+    restart: unless-stopped
+    ports:
+      - "80:80"        # HTTP (Caddy proxy)
+      - "443:443"      # HTTPS (Caddy proxy)
+      - "443:443/udp"  # HTTP/3 (Caddy proxy)
+      - "8080:8080"    # Management UI (Charon)
+      - "2345:2345"    # Delve Debugger
+    environment:
+      - CHARON_ENV=development
+      - CHARON_DEBUG=1
+      - TZ=America/New_York
+      - CHARON_HTTP_PORT=8080
+      - CHARON_DB_PATH=/app/data/charon.db
+      - CHARON_FRONTEND_DIR=/app/frontend/dist
+      - CHARON_CADDY_ADMIN_API=http://localhost:2019
+      - CHARON_CADDY_CONFIG_DIR=/app/data/caddy
+      - CHARON_CADDY_BINARY=caddy
+      - CHARON_IMPORT_CADDYFILE=/import/Caddyfile
+      - CHARON_IMPORT_DIR=/app/data/imports
+      - CHARON_ACME_STAGING=false
+      - FEATURE_CERBERUS_ENABLED=true
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    cap_add:
+      - SYS_PTRACE
+    security_opt:
+      - seccomp:unconfined
+    volumes:
+      - charon_data:/app/data
+      - caddy_data:/data
+      - caddy_config:/config
+      - crowdsec_data:/app/data/crowdsec
+      - /var/run/docker.sock:/var/run/docker.sock:ro # For local container discovery
+      - ./backend:/app/backend:ro # Mount source for debugging
+      # Mount your existing Caddyfile for automatic import (optional)
+#      - <PATH_TO_YOUR_CADDYFILE>:/import/Caddyfile:ro
+#      - <PATH_TO_YOUR_SITES_DIR>:/import/sites:ro # If your Caddyfile imports other files
+    healthcheck:
+      test: ["CMD", "wget", "--no-verbose", "--tries=1", "--spider", "http://localhost:8080/api/v1/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 40s
+
+volumes:
+  charon_data:
+    driver: local
+  caddy_data:
+    driver: local
+  caddy_config:
+    driver: local
+  crowdsec_data:
+    driver: local