When I convert R_13 DWG to JSON there is the change of LAYER.on from 0 to 1. In conversion back to DWG there is 1 still.
Example:
[BLANK.DWG.gz](https://github.com/LibreDWG/libredwg/files/13305124/BLANK.DWG.gz)
[BLANK.json.gz](https://github.com/LibreDWG/libredwg/files/13305125/BLANK.json.gz)

BLANK.DWG:
```
Next object: 13 Handleoff: 0x1 [UMC] Offset: -1413 [MC] @2466
==========================================
Object number: 13/D, Size: 19 [MS], Type: 51 [BS], Address: 2468
Add table record LAYER [13] Decode table record LAYER
handle: 0.1.F [H 5]
EED[0] size: 0 (end)
num_eed: 0
bitsize: 98 [RL]
 Hdlsize: 0x36, hdl_dat: @12.2 - @19.0 (19)
num_reactors: 0 [BL 0]
ownerhandle: (4.1.2) abs:2 [H 330]
xdicobjhandle: (3.0.0) abs:0 [H 360]
--common_size: 52
name: "0" [T 2]
is_xref_ref: 0 [B 0]
is_xref_resolved: 0 [BS 0]
is_xref_dep: 0 [B 0]
xref: (5.0.0) abs:0 [H 0]
frozen: 0 [B 0]
on: 0 [B 0]
frozen_in_new: 0 [B 0]
locked: 0 [B 0]
color.index: 7 [CMC.BS 62]
ltype: (5.1.16) abs:22 [H 6]
 padding: +6
 object_map{F} = 13
 padding: AA/2A (6 bits)
crc: 3335 [RSx]
 check_CRC 2466-2487 = 21: 3335 == 3335
```

BLANK.json:
```
    {
      "object": "LAYER",
      "index": 13,
      "type": 51,
      "handle": [0, 1, 15],
      "size": 19,
      "bitsize": 98,
      "ownerhandle": [4, 1, 2, 2],
      "name": "0",
      "is_xref_ref": 0,
      "is_xref_resolved": 0,
      "is_xref_dep": 0,
      "xref": [5, 0, 0, 0],
      "frozen": 0,
      "on": 1,
      "frozen_in_new": 0,
      "locked": 0,
      "color": 7,
      "ltype": [5, 1, 22, 22]
    },
```
Issue with layer.on in JSON conversions in r13
This is a GitHub Issue
repo:libredwg
owner:LibreDWG
Title : Issue with layer.on in JSON conversions in r13
Issue date:

--- start body ---
When I convert R_13 DWG to JSON there is the change of LAYER.on from 0 to 1. In conversion back to DWG there is 1 still.
Example:
[BLANK.DWG.gz](https://github.com/LibreDWG/libredwg/files/13305124/BLANK.DWG.gz)
[BLANK.json.gz](https://github.com/LibreDWG/libredwg/files/13305125/BLANK.json.gz)

BLANK.DWG:
```
Next object: 13 Handleoff: 0x1 [UMC] Offset: -1413 [MC] @2466
==========================================
Object number: 13/D, Size: 19 [MS], Type: 51 [BS], Address: 2468
Add table record LAYER [13] Decode table record LAYER
handle: 0.1.F [H 5]
EED[0] size: 0 (end)
num_eed: 0
bitsize: 98 [RL]
 Hdlsize: 0x36, hdl_dat: @12.2 - @19.0 (19)
num_reactors: 0 [BL 0]
ownerhandle: (4.1.2) abs:2 [H 330]
xdicobjhandle: (3.0.0) abs:0 [H 360]
--common_size: 52
name: "0" [T 2]
is_xref_ref: 0 [B 0]
is_xref_resolved: 0 [BS 0]
is_xref_dep: 0 [B 0]
xref: (5.0.0) abs:0 [H 0]
frozen: 0 [B 0]
on: 0 [B 0]
frozen_in_new: 0 [B 0]
locked: 0 [B 0]
color.index: 7 [CMC.BS 62]
ltype: (5.1.16) abs:22 [H 6]
 padding: +6
 object_map{F} = 13
 padding: AA/2A (6 bits)
crc: 3335 [RSx]
 check_CRC 2466-2487 = 21: 3335 == 3335
```

BLANK.json:
```
    {
      "object": "LAYER",
      "index": 13,
      "type": 51,
      "handle": [0, 1, 15],
      "size": 19,
      "bitsize": 98,
      "ownerhandle": [4, 1, 2, 2],
      "name": "0",
      "is_xref_ref": 0,
      "is_xref_resolved": 0,
      "is_xref_dep": 0,
      "xref": [5, 0, 0, 0],
      "frozen": 0,
      "on": 1,
      "frozen_in_new": 0,
      "locked": 0,
      "color": 7,
      "ltype": [5, 1, 22, 22]
    },
```
--- end body ---
