Document remote debugging

CONTRIBUTING.md

@@ -101,6 +101,30 @@ convert /media/matthias/Vivlio/screens/scr0002.bmp \
         docs/screenshot-hourly-forecast.jpg
 ```
 
+## Remote debugging
+
+One must first start `gdbserver` on the e-reader:
+
+1. Install [pbterm](https://github.com/Alastor27/pbterm)
+2. Start `taranis.app`
+3. Press the "Home" key to go back to the "desktop"
+4. Start `pbterm`
+4. Run `TARANIS_PID=$(pgrep taranis.app)` to identify the process running
+   `taranis.app`, say 1423
+5. Run `gdbserver --attach :10002 ${TARANIS_PID}`
+
+The e-reader must be connected to Internet and its IP address must be
+known (eg start `ipconfig` in `pbterm`).
+
+On the host computer, start a shell with current working directory the
+root directory of a Git clone of taranis directory. Then start GDB:
+```shell
+./SDK_6.3.0/SDK-B288/usr/bin/arm-linux-gdb -q taranis.app
+```
+
+Under GDB, run `target remote 192.168.1.34:10002` where the IP address
+must updated to the address of the e-reader.
+
 ## References
 
 * https://github.com/pocketbook-free/InkViewDoc

docs/desktop_integration.md

@@ -0,0 +1,45 @@
+# Desktop integration
+
+To customize the application icon and group:
+
+1. One must copy two icons in BMP format on the e-reader (eg under
+   `/mnt/ext1/application/icons/`). One is used to represent the
+   application in the "desktop" view, the other is displayed
+   temporarily when the application is launched.
+
+   Samples icons are provided: [taranis.bmp](./taranis.bmp) and
+   [taranis_f.bmp](./taranis_f.bmp).
+
+2. Then the `/mnt/ext1/system/config/desktop/view.json` file must be
+   edited on the e-reader (the file path may vary depending on the
+   use of profiles):
+
+   ```diff
+   --- "/mnt/ext1/system/profiles/matthias/config/desktop/view.orig.json"	2023-09-30 20:20:34.454795306 +0200
+   +++ "/mnt/ext1/system/profiles/matthias/config/desktop/view.json"	2023-09-30 20:21:06.283101211 +0200
+   @@ -27,7 +27,13 @@
+                "     \"focused_icon\": { \"path\": \"applications/icons/my_calc_icon_f.bmp\" }\n",
+                "   }\n",
+                "end."
+   -        ]
+   +        ],
+   +        "U_Taranis": {
+   +            "path": "/mnt/ext1/applications/taranis.app",
+   +            "title": "Taranis",
+   +            "icon": "/mnt/ext1/applications/icons/taranis.bmp",
+   +            "focused_icon": "/mnt/ext1/applications/icons/taranis_f.bmp"
+   +        }
+        },
+        "view": {
+            "_comment": [
+   @@ -57,7 +63,8 @@
+                        "PB_Onleihe",
+                        "PB_Player",
+                        "PB_RSSNews",
+   -                    "PB_Settings"
+   +                    "PB_Settings",
+   +                    "U_Taranis"
+                    ]
+                },
+                {
+   ```