core: name the unique index on wallet_seeds

The one key per device rule is meant to be lifted later. SQLite cannot drop
a column with an inline UNIQUE, or its automatic index, so lifting it would
have meant rebuilding the table. As a named index it is a DROP INDEX and a
DROP COLUMN.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Rvc3HbiWBTqbAvRT45G5oX

src/Simplex/Chat/Store/Postgres/Migrations/M20260908_wallet_seeds.hs

@@ -15,12 +15,13 @@ CREATE TABLE wallet_seeds (
   -- see the SQLite migration
   next_account_index BIGINT NOT NULL DEFAULT 0,
   -- one key per device for now
-  single_seed SMALLINT NOT NULL DEFAULT 1 UNIQUE
+  single_seed SMALLINT NOT NULL DEFAULT 1
 );
 
 ALTER TABLE users ADD COLUMN wallet_seed_id BIGINT REFERENCES wallet_seeds ON DELETE RESTRICT;
 ALTER TABLE users ADD COLUMN wallet_account_index BIGINT;
 
+CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
 CREATE INDEX idx_users_wallet_seed_id ON users(wallet_seed_id);
 |]
 

src/Simplex/Chat/Store/Postgres/Migrations/chat_schema.sql

@@ -1918,11 +1918,6 @@ ALTER TABLE ONLY test_chat_schema.wallet_seeds
 
 
 
-ALTER TABLE ONLY test_chat_schema.wallet_seeds
-    ADD CONSTRAINT wallet_seeds_single_seed_key UNIQUE (single_seed);
-
-
-
 ALTER TABLE ONLY test_chat_schema.xftp_file_descriptions
     ADD CONSTRAINT xftp_file_descriptions_pkey PRIMARY KEY (file_descr_id);
 
@@ -2676,6 +2671,10 @@ CREATE INDEX idx_users_wallet_seed_id ON test_chat_schema.users USING btree (wal
 
 
 
+CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON test_chat_schema.wallet_seeds USING btree (single_seed);
+
+
+
 CREATE INDEX idx_xftp_file_descriptions_user_id ON test_chat_schema.xftp_file_descriptions USING btree (user_id);
 
 

src/Simplex/Chat/Store/SQLite/Migrations/M20260908_wallet_seeds.hs

@@ -16,12 +16,13 @@ CREATE TABLE wallet_seeds (
   -- the order they ask for a key, not the order they had
   next_account_index INTEGER NOT NULL DEFAULT 0,
   -- one key per device for now
-  single_seed INTEGER NOT NULL DEFAULT 1 UNIQUE
+  single_seed INTEGER NOT NULL DEFAULT 1
 ) STRICT;
 
 ALTER TABLE users ADD COLUMN wallet_seed_id INTEGER REFERENCES wallet_seeds ON DELETE RESTRICT;
 ALTER TABLE users ADD COLUMN wallet_account_index INTEGER;
 
+CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
 CREATE INDEX idx_users_wallet_seed_id ON users(wallet_seed_id);
 |]
 

src/Simplex/Chat/Store/SQLite/Migrations/chat_schema.sql

@@ -862,7 +862,7 @@ CREATE TABLE wallet_seeds(
   -- the order they ask for a key, not the order they had
   next_account_index INTEGER NOT NULL DEFAULT 0,
   -- one key per device for now
-  single_seed INTEGER NOT NULL DEFAULT 1 UNIQUE
+  single_seed INTEGER NOT NULL DEFAULT 1
 ) STRICT;
 CREATE INDEX contact_profiles_index ON contact_profiles(
   display_name,
@@ -1398,6 +1398,7 @@ CREATE INDEX idx_files_roster_transfer_id ON files(roster_transfer_id);
 CREATE INDEX idx_chat_items_item_signed_by_group_member_id ON chat_items(
   item_signed_by_group_member_id
 );
+CREATE UNIQUE INDEX idx_wallet_seeds_single_seed ON wallet_seeds(single_seed);
 CREATE INDEX idx_users_wallet_seed_id ON users(wallet_seed_id);
 CREATE TRIGGER on_group_members_insert_update_summary
 AFTER INSERT ON group_members

src/Simplex/Chat/Wallet.hs

@@ -2,8 +2,8 @@
 
 -- | BIP-39 seeds and the keys derived from them.
 --
--- One key per name, not one per profile, so that exporting a name's key hands
--- over that name only.
+-- Two layers: one account path per profile, and one key per name under it. A
+-- per-profile key would hand over every name that profile owns.
 module Simplex.Chat.Wallet
   ( SeedId (..),
     WalletSeed (..),