Vim9: Internal error with `this` queried in variable initialisers

[zzzyxwvut]

Steps to reproduce

(Before the failing class examples, I have included a couple
of working class examples named TestPassing*.)

Example 1:

vim9script

class TestPassing1
    const one: number = TestPassing1.One(this)

    static def One(that: TestPassing1): number
	return 1
    enddef
endclass

echo TestPassing1.One(TestPassing1.new())

class TestPassing2
    const one: number = 1
    const two: number = TestPassing2.Two(this)

    static def Two(that: TestPassing2): number
	return that.one + 1
    enddef
endclass

echo TestPassing2.Two(TestPassing2.new())


class Test2
    const two: number = Test2.Two(this)
    const one: number = 1

    static def Two(that: Test2): number
	return that.one + 2
    enddef
endclass

# E340
echo Test2.Two(Test2.new())

Example 2:

vim9script

class TestPassing1
    const Id: func(any): any = ((_) => (v) => v)(this)

    static def Id(that: TestPassing1): func(any): any
	return that.Id
    enddef
endclass

echo TestPassing1.Id(TestPassing1.new())(1)
echo TestPassing1.new().Id(1)

class Test1
    const Id: func(any): any = ((that) => (_) => that)(this)

    static def Id(that: Test1): func(any): any
	return that.Id
    enddef
endclass

# E340
const Id0: func(any): any = Test1.Id(Test1.new())
# E340
const Id1: func(any): any = Test1.new().Id

class Test2
    const Id: any = Test2.Id(this)

    static def Id(that: Test2): any
	return that.Id
    enddef
endclass

# E340
const Id2: any = Test2.Id(Test2.new())
# E340
const Id3: any = Test2.new().Id

Expected behaviour

Each failure can probably be justified on the grounds of
interfering with step 2.

vim/runtime/doc/vim9class.txt

Lines 259 to 263 in 3fa8f77

	The sequence of constructing a new object is:
	1. Memory is allocated and cleared. All values are zero/false/empty.
	2. For each declared object variable that has an initializer, the expression
	is evaluated and assigned to the variable. This happens in the sequence
	the variables are declared in the class.

Do we need a dedicated EXXX for an inappropriate state?

Version of Vim

v9.1.0263

Environment

GNU/Linux Debian (testing/trixie)

Logs and stack traces

No response