preserve allowzero, align, volatile, and addrspace on pointer types

[barry3406]

The ptr_type resolver in analysis.zig only read const_token from ptr_info, and Data.createPointer only set is_const on the InternPool.pointer_type flags. So *allowzero u8, *align(4) u8, *volatile u8 and friends all collapsed to *u8 in inlay hints (and anywhere else that runs through stringifyTypeOf).

This reads volatile_token, allowzero_token, and the literal integer in ast.align_node from ptr_info, plumbs them through createPointerType / Data.createPointer into the IP flags and the .pointer Data fallback, and updates rawStringify so the fallback path matches the InternPool printer.

Address-space resolution from arbitrary expressions still defers to .generic; the field is plumbed through but only the literal alignment integer is currently read.

Regression coverage added in tests/lsp_features/inlay_hints.zig.

Fixes #2603.

[Techatrix]

These tests shouldn't need to go through inlay hints. Instead, add new tests to tests/analysis/pointer.zig which directly target the analysis backend without going through LSP requests.

Example:

diff --git a/tests/analysis/pointer.zig b/tests/analysis/pointer.zig
index 4086f8d4..5aa7acab 100644
--- a/tests/analysis/pointer.zig
+++ b/tests/analysis/pointer.zig
@@ -270,6 +270,9 @@ const ManyPointerWithSentinel = [*:.{}]addrspace(.generic) const packed struct {
 //                                 ^ (packed struct {})()
 //                                               ^^^^^^^^ (AddressSpace)()
 
+const VolatilePointer = *volatile u32;
+//    ^^^^^^^^^^^^^^^ (type)(*volatile u32)
+
 var runtime_index: usize = 5;
 var runtime_u8: u8 = 1;
 var runtime_i8: i8 = -1;

[Techatrix]

We already have a type that can store most pointer attributes. So the number of function parameters can be reduced here:

Suggested change

	size: std.builtin.Type.Pointer.Size,
	sentinel: InternPool.Index,
	is_const: bool,
	is_volatile: bool,
	is_allowzero: bool,
	alignment: u16,
	address_space: std.builtin.AddressSpace,
	elem_ty: Type,
	elem_ty: Type,
	sentinel: InternPool.Index,
	flags: InternPool.Key.Pointer.Flags,

[Techatrix]

We already have a type that can store most pointer attributes.

elem_ty: *Type,
/// `.none` means no sentinel, `.unknown_unknown` means unknown sentinel
sentinel: InternPool.Index,
flags: InternPool.Key.Pointer.Flags,

[Techatrix]

We already have a type that can store most pointer attributes. So the number of function parameters can be reduced here:

Suggested change

	size: std.builtin.Type.Pointer.Size,
	sentinel: InternPool.Index,
	is_const: bool,
	is_volatile: bool,
	is_allowzero: bool,
	alignment: u16,
	address_space: std.builtin.AddressSpace,
	elem_ty: Type,
	elem_ty: Type,
	sentinel: InternPool.Index,
	flags: InternPool.Key.Pointer.Flags,