Fix(EnvAdjust): Properly update sky after cloud texture selection

Problem:
When selecting a new cloud texture in the Personal Lighting floater (LLFloaterEnvironmentAdjust), the sky did not visually update. The code previously only updated LiveSky->setCloudNoiseTextureId() and called mLiveSky->update(), which failed to notify the global LLEnvironment mechanism or the renderer about the new texture.

Cause:
Relying solely on mLiveSky for environment changes is insufficient. To update the live environment layer (ENV_LOCAL) and trigger a render refresh, calls to LLEnvironment::setEnvironment() and LLEnvironment::updateEnvironment() are required.

Solution:
1. Remove an unnecessary null-check for getChild<LLTextureCtrl>, as getChild() never returns null.
2. Clone the current sky settings (mLiveSky->buildClone()) to avoid modifying a shared environment object directly.
3. Apply the new cloud texture ID to the clone.
4. Use LLEnvironment::setEnvironment(ENV_LOCAL, sky_to_set) to apply the updated settings to the user's local environment override.
5. Call LLEnvironment::updateEnvironment(LLEnvironment::TRANSITION_INSTANT, true) to ensure the renderer recognizes and displays the updated texture immediately.
6. Reset the picker control’s value to match the newly applied texture for UI consistency.

Additional Note:
A partial implementation was inadvertently committed earlier (commit`04af042`) due to a local staging error. This commit supersedes that incomplete change by correctly implementing the intended fix.

Result:
Selecting a new cloud texture from LLFloaterEnvironmentAdjust now immediately updates both the in-world sky rendering and the texture preview UI, ensuring consistency and clarity for users.

Testing:
- Open the Personal Lighting floater and select various cloud textures.
- Verify that the sky updates immediately for each new selection.
- Confirm that the texture picker also updates to reflect the selected texture.

indra/newview/llfloaterenvironmentadjust.cpp

@@ -455,26 +455,28 @@ void LLFloaterEnvironmentAdjust::onMoonAzimElevChanged()
 void LLFloaterEnvironmentAdjust::onCloudMapChanged()
 {
     if (!mLiveSky)
-        return;
-
-    // Get the texture picker control
-    LLTextureCtrl* picker_ctrl = getChild<LLTextureCtrl>(FIELD_SKY_CLOUD_MAP);
-    if (!picker_ctrl)
     {
-         // Optional: Log an error if the control isn't found, though unlikely
-         return;
+        return;
     }
 
-    // Get the new texture ID selected by the user
+    LLTextureCtrl* picker_ctrl = getChild<LLTextureCtrl>(FIELD_SKY_CLOUD_MAP);
+
     LLUUID new_texture_id = picker_ctrl->getValue().asUUID();
 
-    // Update the internal sky settings object
-    mLiveSky->setCloudNoiseTextureId(new_texture_id);
+    LLEnvironment::instance().setSelectedEnvironment(LLEnvironment::ENV_LOCAL);
 
-    // Trigger the update for the sky rendering
-    mLiveSky->update();
+    LLSettingsSky::ptr_t sky_to_set = mLiveSky->buildClone();
+    if (!sky_to_set)
+    {
+        return;
+    }
+
+    sky_to_set->setCloudNoiseTextureId(new_texture_id);
+
+    LLEnvironment::instance().setEnvironment(LLEnvironment::ENV_LOCAL, sky_to_set);
+
+    LLEnvironment::instance().updateEnvironment(LLEnvironment::TRANSITION_INSTANT, true);
 
-    // Explicitly refresh the UI picker control to match the applied change
     picker_ctrl->setValue(new_texture_id);
 }