feat(gateway): unify background task runtime and storage

crates/aether-data/schema/generated/mysql/baseline/008_background_tasks.sql

@@ -0,0 +1,42 @@
+-- Generated by aether-data-schema from schema/logical/*.toml.
+-- Do not edit generated files directly; edit logical schema or explicit overrides instead.
+
+CREATE TABLE IF NOT EXISTS background_task_runs (
+    `id` VARCHAR(64) NOT NULL,
+    `task_key` VARCHAR(200) NOT NULL,
+    `kind` VARCHAR(32) NOT NULL,
+    `trigger` VARCHAR(64) NOT NULL,
+    `status` VARCHAR(32) NOT NULL,
+    `attempt` INT NOT NULL DEFAULT 0,
+    `max_attempts` INT NOT NULL DEFAULT 0,
+    `owner_instance` VARCHAR(200),
+    `progress_percent` INT NOT NULL DEFAULT 0,
+    `progress_message` TEXT,
+    `payload_json` JSON,
+    `result_json` JSON,
+    `error_message` TEXT,
+    `cancel_requested` TINYINT(1) NOT NULL DEFAULT 0,
+    `created_by` VARCHAR(200),
+    `created_at_unix_secs` BIGINT NOT NULL,
+    `started_at_unix_secs` BIGINT,
+    `finished_at_unix_secs` BIGINT,
+    `updated_at_unix_secs` BIGINT NOT NULL,
+    PRIMARY KEY (`id`),
+    KEY idx_background_task_runs_task_key (`task_key`),
+    KEY idx_background_task_runs_status (`status`),
+    KEY idx_background_task_runs_kind (`kind`),
+    KEY idx_background_task_runs_created_at (`created_at_unix_secs`)
+);
+
+CREATE TABLE IF NOT EXISTS background_task_events (
+    `id` VARCHAR(64) NOT NULL,
+    `run_id` VARCHAR(64) NOT NULL,
+    `event_type` VARCHAR(64) NOT NULL,
+    `message` TEXT NOT NULL,
+    `payload_json` JSON,
+    `created_at_unix_secs` BIGINT NOT NULL,
+    PRIMARY KEY (`id`),
+    KEY idx_background_task_events_run_id (`run_id`, `created_at_unix_secs`),
+    CONSTRAINT fk_background_task_events_run FOREIGN KEY (`run_id`) REFERENCES background_task_runs (`id`) ON DELETE CASCADE
+);
+

crates/aether-data/schema/generated/mysql/baseline/manifest.txt

@@ -8,3 +8,4 @@
 005_wallet_billing.sql
 006_usage.sql
 007_stats.sql
+008_background_tasks.sql