Added ShadPS4 Flatpak (#1357)

* Adding ShadPS4 Flatpak

* Amended Flatpak installation steps for ShadPS4

* Setting input config, optimize settings management and language support

* Additional amendments for consistency

configs/net.shadps4.ShadPS4/config/shadps4/config.toml

@@ -0,0 +1,68 @@
+# ShadPS4 Settings/Config file
+
+[General]
+isPS4Pro = false
+Fullscreen = false
+playBGM = false
+BGMvolume = 50
+enableDiscordRPC = false
+logType = "async"       # Configures logging synchronization (sync/async)
+logFilter = ""          # Sets the logging category for various logging classes
+userName = "shadPS4"
+updateChannel = "Release"
+showSplash = false
+autoUpdate = false
+separateUpdateEnabled = false
+
+[Input]
+cursorState = 0  # HideCursorState::Idle
+cursorHideTimeout = 5
+backButtonBehavior = "left"
+useSpecialPad = false
+specialPadClass = 1
+
+[GPU]
+# Configures the game window width and height e.g. '800' for OLED Steameck (16:10 Aspect Ratio)
+screenWidth = 1280
+screenHeight = 720
+nullGpu = false         # Disables rendering
+copyGPUBuffers = false
+dumpShaders = false     # Dump shaders that are loaded by the emulator. Dump path: ../user/shader/dumps
+patchShaders = true
+vblankDivider = 1
+
+[Vulkan]
+gpuId = -1
+validation = false
+validation_sync = false
+validation_gpu = false
+rdocEnable = false      # Automatically hook RenderDoc when installed. Useful for debugging shaders and game rendering
+rdocMarkersEnable = false   # Enable automatic RenderDoc event annotation
+crashDiagnostic = false
+
+[Debug]
+DebugDump = false
+CollectShader = false
+
+[GUI]
+theme = 0
+iconSize = 36
+iconSizeGrid = 69
+sliderPos = 0
+sliderPosGrid = 0
+gameTableMode = 0
+mw_width = 1280
+mw_height = 720     # Need to set to '800' for OLED Deck (16:10 Aspect Ratio)
+geometry_x = 400
+geometry_y = 400
+geometry_w = 1280
+geometry_h = 720    # Need to set to '800' for OLED Deck (16:10 Aspect Ratio)
+installDirs = []
+addonInstallDir = ""
+pkgDirs = []
+elfDirs = []
+recentFiles = []
+emulatorLanguage = "en"
+
+[Settings]
+consoleLanguage = 1  # english

configs/net.shadps4.ShadPS4/config/shadps4/inputConfig/default.ini

@@ -0,0 +1,67 @@
+# Default input configuration file, each game may have per-game files too, e.g.
+    ;~/config/shadps4/
+    ;└── inputConfig/
+    ;    ├── default.ini
+    ;    └── [game_id].ini
+
+# Keyboard bindings
+triangle = f
+circle = space
+cross = e
+square = r
+
+pad_up = w, lalt
+pad_up = mousewheelup
+pad_down = s, lalt
+pad_down = mousewheeldown
+pad_left = a, lalt
+pad_left = mousewheelleft
+pad_right = d, lalt
+pad_right = mousewheelright
+
+l1 = rightbutton, lshift
+r1 = leftbutton
+l2 = rightbutton
+r2 = leftbutton, lshift
+l3 = x
+r3 = q
+r3 = middlebutton
+
+options = escape
+touchpad = g
+
+key_toggle = i, lalt
+mouse_to_joystick = right
+mouse_movement_params = 0.5, 1, 0.125
+leftjoystick_halfmode = lctrl
+
+axis_left_x_minus = a
+axis_left_x_plus = d
+axis_left_y_minus = w
+axis_left_y_plus = s
+
+# Controller bindings
+triangle = triangle
+cross = cross
+square = square
+circle = circle
+
+l1 = l1
+l2 = l2
+l3 = l3
+r1 = r1
+r2 = r2
+r3 = r3
+
+pad_up = pad_up
+pad_down = pad_down
+pad_left = pad_left
+pad_right = pad_right
+
+options = options
+touchpad = back
+
+axis_left_x = axis_left_x
+axis_left_y = axis_left_y
+axis_right_x = axis_right_x
+axis_right_y = axis_right_y

configs/steam-deck-romate/userConfigurations.json

@@ -1203,6 +1203,22 @@
       "category":"PlayStation 3",
       "name":"PlayStation 3"
    },
+   {
+      "id": "12345678901234567",
+      "executable": {
+        "path": "\"/usr/bin/flatpak\" run net.shadps4.shadPS4 --no-gui \"${filePath}\"",
+        "arguments": ""
+      },
+      "romDirectory": "roms/ps4",
+      "supportedFileTypes": [
+        "iso",
+        "ISO",
+        "pkg",
+        "PKG"
+      ],
+      "category": "PlayStation 4",
+      "name": "PlayStation 4"
+   },
    {
       "id":"164785656634747068",
       "executable":{