feat: account deletion

internal/db/migrations/00018_create_account_deletion_requests_table.sql

@@ -0,0 +1,45 @@
+-- +goose Up
+-- +goose StatementBegin
+-- Flag on users for fast middleware lookups: once set, every request from the
+-- user is funneled to the "Account Pending Deletion" page until the background
+-- worker finishes wiping their data.
+ALTER TABLE users ADD COLUMN pending_deletion_at TIMESTAMP NULL;
+CREATE INDEX idx_users_pending_deletion_at ON users (pending_deletion_at) WHERE pending_deletion_at IS NOT NULL;
+
+-- Single table that acts as both the work queue AND the permanent audit
+-- record for account deletion requests. Rows are not foreign-keyed to users
+-- because the related user row is hard-deleted on completion; the snapshot
+-- columns preserve who/when/from-where for audit purposes after the data is
+-- gone. Operational columns (status, attempts, last_error) let a background
+-- worker pick the row up, retry on failure, and resume across restarts.
+CREATE TABLE account_deletion_requests (
+    id TEXT PRIMARY KEY NOT NULL,
+    user_id TEXT NOT NULL,
+    email TEXT NOT NULL,
+    name TEXT NULL,
+    reason TEXT NULL,
+    ip_address TEXT NULL,
+    status TEXT NOT NULL DEFAULT 'pending', -- pending | processing | completed | failed
+    attempts INTEGER NOT NULL DEFAULT 0,
+    last_error TEXT NULL,
+    spaces_deleted INTEGER NULL,
+    requested_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    completed_at TIMESTAMP NULL
+);
+
+CREATE INDEX idx_account_deletion_requests_pending
+    ON account_deletion_requests (requested_at)
+    WHERE status IN ('pending', 'processing');
+CREATE INDEX idx_account_deletion_requests_user_id
+    ON account_deletion_requests (user_id);
+CREATE INDEX idx_account_deletion_requests_requested_at
+    ON account_deletion_requests (requested_at DESC);
+-- +goose StatementEnd
+
+-- +goose Down
+-- +goose StatementBegin
+DROP TABLE account_deletion_requests;
+DROP INDEX IF EXISTS idx_users_pending_deletion_at;
+ALTER TABLE users DROP COLUMN pending_deletion_at;
+-- +goose StatementEnd