fix(fs): canonicalize URIs before move

[qin-ctx]

Description

Fix mv vector URI updates when callers use current-user shorthand such as viking://user/memories by canonicalizing source and destination URIs at the VikingFS.mv boundary.

Related Issue

N/A

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

• Canonicalize move source and destination URIs after file destination validation.
• Keep vector URI rewrites aligned with the canonical filesystem URIs and propagate update failures to the existing move rollback.
• Remove the unused L0/L1-only vector move helper and replace its tests with a focused shorthand-URI regression test.

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Screenshots (if applicable)

N/A

Additional Notes

The existing file-destination trailing-slash validation remains before canonicalization so its behavior is unchanged.