Typed tree: create a type's augmentation on first use

[auduchinok]

Every Entity allocated a TyconAugmentation record at construction. An imported IL type never writes to
it: NewILTycon sets exactly one field, tcaug_closed <- true, and most imported types are never asked
for their contents at all.

solution	base MB	change MB	delta
ReSharper.FSharp	384.86	381.62	-3.24 (-0.84%)
FSharp.Compiler.Service	876.83	875.74	-1.09 (-0.12%)
Oxpecker	130.82	129.77	-1.05 (-0.80%)
Fantomas	349.45	348.68	-0.77 (-0.22%)
FsToolkit.ErrorHandling	161.10	160.37	-0.73 (-0.45%)
IcedTasks	96.48	95.88	-0.60 (-0.62%)
Prime	105.40	105.08	-0.32 (-0.30%)
consoleapp	29.19	29.01	-0.18 (-0.62%)

[github-actions]

❗ Release notes required

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@auduchinok,

Caution

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Change path	Release notes path	Description
`src/Compiler`	docs/release-notes/.FSharp.Compiler.Service/11.0.100.md	No release notes found or release notes format is not correct

[github-actions]

🔍 Tooling Safety Check — Affects-Bootstrap, Affects-Compiler-Output
Affects-Bootstrap: EntityFlags bit layout and pickle deserialization changed
Affects-Compiler-Output: PickledBits mask altered, IL metadata serialization path modified

Generated by PR Tooling Safety Check · opus46 3.4M · ◷

[T-Gro]

LGTM