feat: add tasks closes #74

sql/tasks.sql

@@ -0,0 +1,33 @@
+-- drop table if exists tasks
+create table if not exists tasks (
+    id uuid primary key default gen_random_uuid(),
+    user_id uuid references users (id) not null,
+    model_id uuid references models (id) on delete cascade default null,
+
+    -- -2: Failed Running
+    -- -1: Failed Creation
+    --  0: Preparing
+    --  1: TODO
+    --  2: Picked up
+    --  3: Running
+    --  4: Failed
+    status integer default 1,
+    status_message text default '',
+
+    result text default '',
+    
+    -- -1: user said task is wrong
+    --  0: no user input
+    --  1: user said task is ok
+    user_confirmed integer default 0,
+    
+    -- Tells the user if the file has been already compacted into
+    --  embendings
+    compacted integer default 0,
+        
+    -- TODO move the training tasks to here
+    --  1: Classification
+    task_type integer,
+
+    created_on timestamp default current_timestamp
+)