Initial commit: Add project files

db/migrations/0000_building_blocks.sql

@@ -0,0 +1,44 @@
+create schema if not exists building_blocks;
+create schema if not exists signal_engine;
+
+create table if not exists building_blocks.outbox_message (
+    message_id uuid primary key,
+    event_type text not null,
+    schema_version integer not null check (schema_version > 0),
+    payload_json jsonb not null,
+    correlation_id text not null,
+    occurred_at timestamptz not null,
+    payload_hash text not null,
+    published_at timestamptz null,
+    attempt integer not null default 0
+);
+
+create table if not exists building_blocks.inbox_message (
+    consumer text not null,
+    message_id uuid not null,
+    received_at timestamptz not null,
+    payload_hash text not null,
+    primary key (consumer, message_id)
+);
+
+create table if not exists building_blocks.job_run (
+    job_run_id uuid primary key,
+    job_type text not null,
+    job_version integer not null,
+    scope_key text not null,
+    idempotency_key text not null unique,
+    watermark text null,
+    app_version text not null,
+    model_version text null,
+    config_version text null,
+    data_version text null,
+    contract_version text null,
+    status text not null,
+    input_hash text null,
+    output_hash text null,
+    started_at timestamptz null,
+    heartbeat_at timestamptz null,
+    finished_at timestamptz null,
+    error_code text null,
+    trace_id text null
+);