feat: add agent publishing foundation

crates/crank-registry/src/migrations.rs

@@ -191,5 +191,78 @@ pub async fn apply_postgres(pool: &PgPool) -> Result<(), sqlx::Error> {
     .execute(pool)
     .await?;
 
+    query(
+        "create table if not exists agents (
+            id text primary key,
+            workspace_id text not null references workspaces(id) on delete cascade,
+            slug text not null,
+            display_name text not null,
+            description text not null,
+            status text not null,
+            current_draft_version integer not null default 1,
+            latest_published_version integer null,
+            created_at timestamptz not null,
+            updated_at timestamptz not null,
+            published_at timestamptz null
+        )",
+    )
+    .execute(pool)
+    .await?;
+
+    query(
+        "create unique index if not exists agents_workspace_slug_idx on agents(workspace_id, slug)",
+    )
+    .execute(pool)
+    .await?;
+
+    query(
+        "create table if not exists agent_versions (
+            agent_id text not null references agents(id) on delete cascade,
+            version integer not null,
+            status text not null,
+            instructions_json jsonb not null,
+            tool_selection_policy_json jsonb not null,
+            created_at timestamptz not null,
+            primary key (agent_id, version)
+        )",
+    )
+    .execute(pool)
+    .await?;
+
+    query(
+        "create table if not exists agent_operation_bindings (
+            agent_id text not null references agents(id) on delete cascade,
+            agent_version integer not null,
+            operation_id text not null references operations(id) on delete cascade,
+            operation_version integer not null,
+            tool_name text not null,
+            tool_title text not null,
+            tool_description_override text null,
+            enabled boolean not null default true,
+            foreign key (agent_id, agent_version) references agent_versions(agent_id, version) on delete cascade,
+            foreign key (operation_id, operation_version) references operation_versions(operation_id, version) on delete cascade
+        )",
+    )
+    .execute(pool)
+    .await?;
+
+    query(
+        "create unique index if not exists agent_bindings_tool_name_idx on agent_operation_bindings(agent_id, agent_version, tool_name)",
+    )
+    .execute(pool)
+    .await?;
+
+    query(
+        "create table if not exists published_agents (
+            agent_id text primary key references agents(id) on delete cascade,
+            version integer not null,
+            published_at timestamptz not null,
+            published_by text null,
+            foreign key (agent_id, version) references agent_versions(agent_id, version) on delete cascade
+        )",
+    )
+    .execute(pool)
+    .await?;
+
     Ok(())
 }