Add persistent global mouse sensitivity setting with slider

MouseSensitivity is a static, PlayerPrefs-backed multiplier (default 1,
clamped 0.1-4.0) that scales the mouse-look delta in the FreeCam,
FirstPerson and ThirdPerson controllers. Writes flush immediately so the
value survives a hard build exit. MouseSensitivitySlider binds the
Settings-panel slider to it (range read from the inspector) and mirrors
the value into its label, syncing on panel open via OnEnable.

Main.unity now contains the session-manager canvas directly (the
Online Session Manager prefab was unpacked) and wires the slider binder.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/Scripts/FirstPersonController.cs

@@ -113,7 +113,7 @@ public class FirstPersonController : MonoBehaviour
 
     void LookTick()
     {
-        Vector2 delta = ReadMouseDelta();
+        Vector2 delta = ReadMouseDelta() * MouseSensitivity.Multiplier;
         _yaw += delta.x * horizontalSensitivity;
         float vs = verticalSensitivity * (invertY ? 1f : -1f);
         _pitch = Mathf.Clamp(_pitch + delta.y * vs, -maxPitch, maxPitch);

Assets/Scripts/FreeCamController.cs

@@ -109,7 +109,7 @@ public class FreeCamController : MonoBehaviour
 
     void LookTick()
     {
-        Vector2 delta = ReadMouseDelta();
+        Vector2 delta = ReadMouseDelta() * MouseSensitivity.Multiplier;
         _yaw += delta.x * horizontalSensitivity;
         float vs = verticalSensitivity * (invertY ? 1f : -1f);
         _pitch = Mathf.Clamp(_pitch + delta.y * vs, -maxPitch, maxPitch);

Assets/Scripts/MouseSensitivity.cs

@@ -0,0 +1,46 @@
+using System;
+using UnityEngine;
+
+/// Global mouse look-around sensitivity multiplier, shared by every camera
+/// controller (FreeCam, FirstPerson, ThirdPersonOrbit). 1 = unchanged baseline.
+/// Persisted per-machine via PlayerPrefs so the setting survives restarts.
+public static class MouseSensitivity
+{
+    public const float Default = 1f;
+    public const float Min = 0.1f;
+    public const float Max = 4f;
+
+    const string PrefKey = "Settings.MouseSensitivity";
+
+    static bool _loaded;
+    static float _multiplier = Default;
+
+    /// Fires whenever the multiplier changes (UI may run before the avatar spawns).
+    public static event Action<float> Changed;
+
+    public static float Multiplier
+    {
+        get
+        {
+            if (!_loaded)
+            {
+                _loaded = true;
+                _multiplier = Mathf.Clamp(PlayerPrefs.GetFloat(PrefKey, Default), Min, Max);
+            }
+            return _multiplier;
+        }
+        set
+        {
+            float v = Mathf.Clamp(value, Min, Max);
+            _loaded = true;
+            if (Mathf.Approximately(v, _multiplier)) return;
+            _multiplier = v;
+            PlayerPrefs.SetFloat(PrefKey, v);
+            // Flush to disk now so the setting survives a hard kill (build), not
+            // only a clean quit. Settings changes are rare user actions, so the
+            // extra write is negligible.
+            PlayerPrefs.Save();
+            Changed?.Invoke(v);
+        }
+    }
+}

Assets/Scripts/MouseSensitivity.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: 5dc578039be8b9e48a2260d640ffcfc1

Assets/Scripts/MouseSensitivitySlider.cs

@@ -0,0 +1,37 @@
+using TMPro;
+using UnityEngine;
+using UnityEngine.UI;
+
+/// Binds a UI Slider (and optional value label) to the global MouseSensitivity
+/// multiplier. The slider's range is authored in the inspector (0.1 - 4.0);
+/// this only reads/writes the value so scene-side range edits are respected.
+public class MouseSensitivitySlider : MonoBehaviour
+{
+    [SerializeField] private Slider slider;
+    [Tooltip("Optional TMP label showing the current multiplier (e.g. \"1,00\").")]
+    [SerializeField] private TMP_Text valueLabel;
+
+    void OnEnable()
+    {
+        if (!slider) return;
+        slider.SetValueWithoutNotify(MouseSensitivity.Multiplier);
+        UpdateLabel(MouseSensitivity.Multiplier);
+        slider.onValueChanged.AddListener(OnSliderChanged);
+    }
+
+    void OnDisable()
+    {
+        if (slider) slider.onValueChanged.RemoveListener(OnSliderChanged);
+    }
+
+    void OnSliderChanged(float value)
+    {
+        MouseSensitivity.Multiplier = value;
+        UpdateLabel(value);
+    }
+
+    void UpdateLabel(float value)
+    {
+        if (valueLabel) valueLabel.text = value.ToString("0.00");
+    }
+}

Assets/Scripts/MouseSensitivitySlider.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: fc6da376d2cfebe47beeb9b6012e76dd

Assets/Scripts/ThirdPersonOrbitInput.cs

@@ -103,7 +103,7 @@ public class ThirdPersonOrbitInput : MonoBehaviour
 
         if (modeWantsLook && !LookSuppressed)
         {
-            Vector2 delta = ReadMouseDelta();
+            Vector2 delta = ReadMouseDelta() * MouseSensitivity.Multiplier;
             Vector2 raw = new Vector2(
                 delta.x * horizontalSensitivity,
                 delta.y * verticalSensitivity * (invertY ? 1f : -1f));