fix: Order child deletion before parent move

[shepilov]

Problem

Fixes #2450.

The stopped-client scenario test/scenarios/move_dir_and_replace_subfile/local/stopped can create dst/file-conflict-... instead of preserving the replaced child at dst/file.

The scenario starts with src/ and src/file. While Twake Desktop is stopped, the user moves src to dst, replaces dst/file with a new file, then starts sync. The final state should keep the new child as dst/file and trash the old child identity.

Root cause

The sync dependency graph knew how to order some parent/child moves and additions, but it did not express that a deleted child from a directory move source must be applied before the parent directory move.

Without that dependency, sync could move the old remote child from src/file to dst/file as part of the parent directory move. The later upload of the new dst/file then saw an active file at the same path and was resolved as a conflict.

Changes

• Add a same-side dependency rule in compareChanges: when a child deletion is inside a directory move source path, the deletion must run before the parent move.
• Add unit coverage for both argument orders.
• Add dependency-graph coverage for the full problematic order: ADD(dst/file), MOVE(src -> dst), DEL(src/file) is expanded as DEL(src/file), MOVE(src -> dst), ADD(dst/file).