Add local-cache fallback for namespace-to-schema resolution

[mariuszlipinski]

Summary

• Add local-cache fallback for namespace-to-schema resolution (for trusted hosts only).
• Improve taxonomy namespace resolution by normalizing namespace keys.

Why

• Prevent namespace lookup misses caused by trailing slashes/format differences.
• Resolve more taxonomies from already cached schemas.
• Keep behavior safe by limiting fallback to trusted hosts.

Validation

• ruff check xbrl
• ruff format --check xbrl
• mypy xbrl --check-untyped-defs
• pytest tests/

[manusimidt]

Hi @mariuszlipinski thanks a lot for the PR, looks like an interesting one!
I am running out of time rn, I try to review and merge it on sunday.
Thanks!

[mariuszlipinski]

I think that if Resolve taxonomy namespaces from trusted schema references (PR #182) was accepted, then this one should be also. They go hand in hand.