Add monitoring service and database schema

- Implement monitoring service with heartbeat, lease tasks, resume tasks, and task result handling.
- Create monitoring time utilities for business date calculations.
- Add unit tests for date window resolution and business day handling.
- Define database schema for monitoring-related tables including quotas, daily reports, and task management.
- Establish migration scripts for creating and dropping monitoring tables.

server/Makefile

@@ -1,6 +1,7 @@
-.PHONY: dev-init dev-api migrate-up migrate-down migrate-create sqlc-generate tenant-scope-guard lint test tidy seed
+.PHONY: dev-init dev-api migrate-up migrate-down migrate-monitoring-up migrate-monitoring-down migrate-create sqlc-generate tenant-scope-guard lint test tidy seed
 
 DB_URL ?= postgres://geo:geo_dev@localhost:5432/geo?sslmode=disable
+MONITORING_DB_URL ?= postgres://geo:geo_dev@localhost:5433/geo_monitoring?sslmode=disable
 MIGRATE_CMD ?= go run -tags postgres github.com/golang-migrate/migrate/v4/cmd/migrate@v4.19.1
 
 dev-init: ## Start infra, run migrations, seed data
@@ -8,6 +9,7 @@ dev-init: ## Start infra, run migrations, seed data
 	@echo "Waiting for postgres..."
 	@sleep 3
 	$(MAKE) migrate-up
+	$(MAKE) migrate-monitoring-up
 	$(MAKE) seed
 
 dev-api: ## Run tenant-api server
@@ -19,6 +21,12 @@ migrate-up: ## Run all pending migrations
 migrate-down: ## Rollback last migration
 	$(MIGRATE_CMD) -path migrations -database "$(DB_URL)" down 1
 
+migrate-monitoring-up: ## Run all pending monitoring migrations
+	$(MIGRATE_CMD) -path migrations_monitoring -database "$(MONITORING_DB_URL)" up
+
+migrate-monitoring-down: ## Rollback last monitoring migration
+	$(MIGRATE_CMD) -path migrations_monitoring -database "$(MONITORING_DB_URL)" down 1
+
 migrate-create: ## Create new migration (usage: make migrate-create NAME=xxx)
 	$(MIGRATE_CMD) create -ext sql -dir migrations -seq $(NAME)