feat(store): миграция sessions/password + методы users/sessions/projects

Фаза 2, Task 1: добавлена таблица sessions и nullable password_hash у
users, sqlc-запросы и *Store-обёртки (CreateUser, GetUserByEmail,
CreateProjectForUser, GetProjectOwned, GetUserProject, CreateSession,
GetSessionUser, DeleteSession, RegisterUser в транзакции), интеграционные
тесты на testcontainers.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwxdSt4reTm7Dj1oxRvpP3

internal/store/db/sessions.sql.go

@@ -0,0 +1,54 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.31.1
+// source: sessions.sql
+
+package db
+
+import (
+	"context"
+
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5/pgtype"
+)
+
+const createSession = `-- name: CreateSession :exec
+INSERT INTO sessions (id, user_id, token_hash, expires_at) VALUES ($1, $2, $3, $4)
+`
+
+type CreateSessionParams struct {
+	ID        uuid.UUID          `json:"id"`
+	UserID    uuid.UUID          `json:"user_id"`
+	TokenHash string             `json:"token_hash"`
+	ExpiresAt pgtype.Timestamptz `json:"expires_at"`
+}
+
+func (q *Queries) CreateSession(ctx context.Context, arg CreateSessionParams) error {
+	_, err := q.db.Exec(ctx, createSession,
+		arg.ID,
+		arg.UserID,
+		arg.TokenHash,
+		arg.ExpiresAt,
+	)
+	return err
+}
+
+const deleteSession = `-- name: DeleteSession :exec
+DELETE FROM sessions WHERE token_hash = $1
+`
+
+func (q *Queries) DeleteSession(ctx context.Context, tokenHash string) error {
+	_, err := q.db.Exec(ctx, deleteSession, tokenHash)
+	return err
+}
+
+const getSessionUser = `-- name: GetSessionUser :one
+SELECT user_id FROM sessions WHERE token_hash = $1 AND expires_at > now()
+`
+
+func (q *Queries) GetSessionUser(ctx context.Context, tokenHash string) (uuid.UUID, error) {
+	row := q.db.QueryRow(ctx, getSessionUser, tokenHash)
+	var user_id uuid.UUID
+	err := row.Scan(&user_id)
+	return user_id, err
+}