Added Nav Bar and Refactor some activities to fragments

- Added a nav bar to go to customer chat and staff profile
- refactored the activities for pets, suppliers, services and it's detailed activates to make the newly added nav bar to work on all screens.

TODO:
- add functionalities to profile and chat fragments
- change theme of app to stay consistent with desktop app
- change text so it uses String.xml values

app/src/main/res/layout/fragment_supplier.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="#F5F5F5">
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/recyclerViewSuppliers"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:padding="8dp"/>
+
+    <com.google.android.material.floatingactionbutton.FloatingActionButton
+        android:id="@+id/fabAddSupplier"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom|end"
+        android:layout_margin="16dp"
+        android:contentDescription="Add Supplier"
+        app:srcCompat="@android:drawable/ic_input_add"/>
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>