Add a way to reset password (WIP)

backend/sql/version_1.sql

@@ -16,6 +16,11 @@ CREATE TABLE [User] (
     [creation_datetime] TEXT NOT NULL, -- Updated when the validation email is sent.
     [validation_token] TEXT, -- If not null then the user has not validated his account yet.
 
+    [password_reset_token] TEXT, -- If not null then the user can reset its password.
+    -- The time when the reset token has been created.
+    -- Password can only be reset during a certain duration after this time.
+    [password_reset_datetime] TEXT,
+
     [is_admin] INTEGER NOT NULL DEFAULT FALSE
 ) STRICT;
 
@@ -67,16 +72,15 @@ CREATE TABLE [RecipeTag] (
     [recipe_id] INTEGER NOT NULL,
     [tag_id] INTEGER NOT NULL,
 
+    UNIQUE([recipe_id], [tag_id]),
+
     FOREIGN KEY([recipe_id]) REFERENCES [Recipe]([id]) ON DELETE CASCADE,
     FOREIGN KEY([tag_id]) REFERENCES [Tag]([id]) ON DELETE CASCADE
 ) STRICT;
 
 CREATE TABLE [Tag] (
     [id] INTEGER PRIMARY KEY,
-    [recipe_tag_id] INTEGER,
-    [name] TEXT NOT NULL,
-
-    FOREIGN KEY([recipe_tag_id]) REFERENCES [RecipeTag]([id]) ON DELETE SET NULL
+    [name] TEXT NOT NULL
 ) STRICT;
 
 CREATE UNIQUE INDEX [Tag_name_index] ON [Tag] ([name]);