Fix 21793 - Cannot initialize shared member with -preview=nosharedaccess

[MoonlightSentinel]

Move the shared check after the ConstructExp lowering (which may ignore shared) and allow calls to shared functions in DotVarExp's

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21793	normal	Cannot initialize shared member with -preview=nosharedaccess

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#12348"