`generic` inheritance does not work

Nobody has claimed this yet.

The second case

```lua
Core = {};

---@class Rotation
---@field Enabled boolean
local Rotation = {}

function Rotation:OnLoad() end
function Rotation:OnUnload() end

---@class RotationEngine
Core.RotationEngine = {}

---@generic T
---@param name `T`
---@return T|Rotation rotation
function Core.RotationEngine.AddRotation(name) end

---@class MyRotation
---@field testfield table
local MyRotation = {};

function MyRotation:Test() end

local rotation = Core.RotationEngine.AddRotation("MyRotation");

---@param self MyRotation
---@return boolean
local function myFunc(self) end

local a = myFunc(rotation);

```

In the first case, in the `MyRotation` class, we seek methods of the `Rotation` class,


but also an error `Cannot assign MyRotation|Rotation to parameter MyRotation.Lua Diagnostics.(param-type-mismatch)`


The second case

```lua
Core = {};

---@class Rotation
---@field Enabled boolean
local Rotation = {}

function Rotation:OnLoad() end
function Rotation:OnUnload() end

---@class RotationEngine
Core.RotationEngine = {}

---@generic T: Rotation
---@param name `T`
---@return T rotation
function Core.RotationEngine.AddRotation(name) end

---@class MyRotation
---@field testfield table
local MyRotation = {};

function MyRotation:Test() end

local rotation = Core.RotationEngine.AddRotation("MyRotation");

---@param self MyRotation
---@return boolean
local function myFunc(self) end

local a = myFunc(rotation);
```

In the second case there is no inheritance


and there is no error either


Start by reproducing both Lua snippets from the issue and compare the inferred type of rotation, method completion, and diagnostics. Trace the generic return-type inference and class-inheritance handling involved in AddRotation. Done means the intended inherited members are available and the incorrect MyRotation|Rotation type mismatch is resolved without losing the second case's behavior.

Written by the indexing model from the issue text.