feat: update flatpak manifest

The new manifest yields much better flatpaks for our end-users:

 - Fewer permissions are requested
 - Fixed app icon
 - Release build instead of a debug build

org.kde.keysmith.json

@@ -4,16 +4,14 @@
     "runtime-version": "5.15",
     "sdk": "org.kde.Sdk",
     "command": "keysmith",
+    "rename-icon": "keysmith",
     "tags": ["nightly"],
     "desktop-file-name-suffix": " (Nightly)",
     "finish-args": [
         "--share=ipc",
-        "--share=network",
-        "--socket=x11",
+        "--socket=fallback-x11",
         "--socket=wayland",
-        "--device=dri",
-        "--filesystem=home",
-        "--talk-name=org.freedesktop.Notifications"
+        "--device=dri"
     ],
     "separate-locales": false,
 
@@ -26,13 +24,15 @@
                 {
                     "type": "git",
                     "url": "https://github.com/jedisct1/libsodium.git",
-                    "tag": "1.0.18"
+                    "tag": "1.0.18",
+                    "commit": "4f5e89fa84ce1d178a6765b8b46f2b6f91216677"
                 }
             ]
         },
         {
             "name": "org.kde.keysmith",
             "buildsystem": "cmake-ninja",
+            "config-opts": [ "-DBUILD_TESTING=OFF", "-DCMAKE_BUILD_TYPE=RelWithDebInfo" ],
             "builddir": true,
             "sources": [ { "type": "dir", "path": ".", "skip": [".git"] } ]
         }

org.kde.keysmith.json.license

@@ -1,3 +1,4 @@
 SPDX-License-Identifier: BSD-2-Clause
 SPDX-FileCopyrightText: 2019 Bhushan Shah <bshah@kde.org>
 SPDX-FileCopyrightText: 2019-2020 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
+SPDX-FileCopyrightText: 2021 Devin Lin <espidev@gmail.com>