ochaind: Track HTLC status correctly across channel closes

### Issue and Steps to Reproduce

This is a phenomenon we have observed a couple of times in Greenlight:

1. We initiate a payment
2. The payment has some HTLC that times out (likely due to the signer
not being present, but getting stuck downstream is also a common
cause)
3. The channel then closes because it hits the HTLC deadline
4. The HTLC outputs get resolved / swept correctly, but the HTLC
still shows up as pending, and will never be resolved.

The HTLC should instead be marked as either `complete` or `timeout`
when `onchaind` reports the HTLC output being swept to `lightningd`
and `lightningd` ought to store this in the DB as well.

### `getinfo` output

```javascript
{
"id": "03442386091363708e6e3bcda4dd978d7777743fde7a4990166cdec2e5065149f1",
"alias": "BLUESEAGULL-v24.02gl1",
"color": "034423",
"num_peers": 1,
"num_active_channels": 1,
"version": "v24.02gl1",
"lightning_dir": "/tmp/bitcoin",
"our_features": {
"init": "08a0800a8a59a1",
"node": "88a0800a8a59a1",
"invoice": "02000002024100",
"channel": ""
},
"blockheight": 870397,
"network": "bitcoin",
"fees_collected_msat": {
"msat": 0
},
"warning_lightningd_sync": "Still loading latest blocks from bitcoind."
}
```

Ignore the sync warning, it is a peculiarity of how we set up
Greenlight's bitcoin backends.