[Feature request]: Add ability to define enums without setting variable

How are you using the lua-language-server?

NeoVim

Which OS are you using?

Linux

What is the issue affecting?

Annotations

Expected Behaviour

Enum fields are defined and shown when hovering over the variable they are assigned to.

Actual Behaviour

Not all enum fields are picked up. The fields that are picked up are displayed as unknown.

Reproduction steps

Not needed for a feature request.

Additional Notes

When using Neovim, the standard library that comes with it is defined in files which use any a lot. An issue that I have ran into when trying to define an enum for a table that looks like the following is that it just won't work.

Table I am trying to define (this is what is show when hovering):

vim.log.levels: {
    TRACE: integer = 0,
    DEBUG: integer = 1,
    INFO: integer = 2,
    WARN: integer = 3,
    ERROR: integer = 4,
    OFF: integer = 5,
}

I have tried a couple of ways to define an enum to cover this:

-- Method 1
---@enum LogLevels
---| '0'
---| '1'
---| '2'
---| '3'
---| '4'
---| '5'

-- Method 2
---@enum LogLevels
---| TRACE = '0'
---| DEBUG = '1'
---| INFO = '2'
---| WARN = '3'
---| ERROR = '4'
---| OFF = '5'

-- Method 3
---@enum LogLevels
---| TRACE: 0
---| DEBUG: 1
---| INFO: 2
---| WARN: 3
---| ERROR: 4
---| OFF: 5

-- Method 4
---@enum LogLevels
---| TRACE: integer = 0 # Trace level
---| DEBUG: integer = 1 # Debug level
---| INFO: integer = 2 # Info level
---| WARN: integer = 3 # Warn level
---| ERROR: integer = 4 # Error level
---| OFF: integer = 5 # Off level

And then, when trying to set the variable to the enum vim.log.levels, I have done a couple of things as well:

-- Method 1
---@type LogLevels
M.levels = vim.log.levels --[=[@as LogLevels]=]

-- Method 2
---@type LogLevels
local tmp_levels = vim.log.levels --[=[@as LogLevels]=]
---@type LogLevels
M.levels = tmp_levels

When doing any of these, if I hover over M.levels only 3 of the fields are shown:

(field) M.levels: LogLevels {
    ERROR: unknown,
    INFO: unknown,
    WARN: unknown,
}

I am aware that the following can be done to do something similar.
However, I would like to be able to add descriptions to fields and I would like to not see a table literal in the inlayhints.
Also, this won't work as a parameter type for a function because it would expect a table literal instead of an enum field.

This works for type declaration:

---@alias LogLevels { TRACE: 0, DEBUG: 1, INFO: 2, WARN: 3, ERROR: 4, OFF: 5 }

---@type LogLevels
M.levels = vim.log.levels

Log File

Not needed for a feature request.

首先在 Neovim/Lua-language-server 环境中复现 enum 声明和赋值示例，然后跟踪 @enum 注解、类型赋值和悬停输出的处理方式。完成的标准是：可以在不为变量赋值的情况下声明 enum，保留命名字段和描述，并且能够作为 vim.log.levels 和函数参数的类型使用。