fix: update import paths when .flyde files are moved or renamed

[maoshuorz]

Summary

Fixes #112 — broken imports after moving files.

/claim #112

When a .flyde or .flyde.ts file is moved or renamed in VS Code, all .flyde files that reference it via source.type: "file" now have their relative paths automatically updated to point to the new location.

Problem

When a user creates a flow that imports another .flyde file (e.g., ./ChildFlow.flyde) and then moves that imported file to a different folder, the import path breaks because the relative path stored in source.data is no longer valid.

Solution

Added a workspace.onDidRenameFiles handler in the VS Code extension (updateImportsOnFileMove.ts) that intercepts file move/rename events and automatically updates import paths in all affected .flyde files.

Three scenarios handled:

1. Imported file is moved — All .flyde files referencing the moved file get their source.data paths recalculated relative to the new location.

2. Flow file itself is moved to a different directory — Its internal source.type: "file" references are recalculated relative to the new directory.

3. Both files move simultaneously — The handler cross-references the rename list so paths resolve correctly even when multiple related files are moved at once.

Implementation details:

• Listens to workspace.onDidRenameFiles (fires after the move completes)
• Only processes moves of .flyde and .flyde.ts files
• Parses affected flows with the yaml library (already a dependency via @flyde/loader)
• Handles inline visual nodes recursively
• Uses POSIX-style relative paths (e.g., ./subfolder/Child.flyde) matching the existing convention
• Shows an info message when paths are updated so the user knows what changed

Files changed

• vscode/src/updateImportsOnFileMove.ts — New file with the import update logic
• vscode/src/extension.ts — Registers the handler on extension activation

Test plan

• Create Parent.flyde that imports ./Child.flyde via source: { type: file, data: ./Child.flyde }
• Move Child.flyde to a subfolder — verify Parent.flyde updates to ./subfolder/Child.flyde
• Move Parent.flyde to a subfolder — verify its reference updates relative to new location
• Move a .flyde.ts code node file — verify referencing flows update
• Move unrelated files — verify no .flyde files are modified