chore: remove 30+ unused variable declarations in ProjectEditor.vue

[t0kubetsu]

Problem

src/views/ProjectEditor.vue imports and destructures many composable return values that are never referenced in the template or script logic. ESLint reports 33 no-unused-vars errors in this file alone, for example:

• setBaseUrl (imported from proxmox api, never called)
• removeNodes (destructured from useVueFlow, never used)
• All 12 start/stop/pause/resume VM handlers (handleBundleCoreProxmoxConfigureDefault_*)
• All 3 delete handlers
• All 3 create handlers
• All 6 snapshot revert/create handlers
• All 4 current_action_* variables

These were likely destructured in preparation for wiring up UI buttons that were not yet implemented, or left behind after a refactor.

Expected

• Dead imports and destructured variables removed
• ESLint passes with 0 errors on this file

Notes

The composables themselves should be retained — only the unused destructured bindings in ProjectEditor.vue need to be cleaned up or properly wired to the template.