Temporary tables still visible after releasing connection to pool

まだ誰も着手していません。

It seems like releasing a connection back to the pool doesn't entirely reset its state in a way that makes it brand new for the next user. Is it expected that temporary tables are still visible? Temporary tables in PostgreSQL are dropped after the session exits but wondering if there is a missing incantation in `Connection.reset()` that will allow it to be reused.

```python
import asyncio

import asyncpg

async def main():
pool = await asyncpg.create_pool(
...
min_size=1,
max_size=1,
)

async with pool.acquire() as conn:
await conn.execute("CREATE TEMPORARY TABLE foo(id INT PRIMARY KEY)")

async with pool.acquire() as conn:
await conn.execute("CREATE TEMPORARY TABLE foo(id INT PRIMARY KEY)") # DuplicateTableException

asyncio.run(main())

```

Start by running the supplied asyncio reproduction with a one-connection pool, then inspect Connection.reset() and the pool acquire/release path. Determine whether releasing a connection should remove the temporary table, and make the behavior match the documented pool-reset expectations, with the reproduction serving as the completion check.

索引モデルが issue の本文から書いたものです。