Workspace-level storage isolation & attachment cleanup

[TechHutTV]

Summary

• Workspace-scoped storage: All file writes (drive files, uploads, avatars, wiki images, backup imports) are now nested under {workspaceId}/ on disk, enabling per-workspace management, cleanup, and data export.
• Remove direct attachment uploads: The separate attachment upload endpoint and its storage scheme (attachments/ category) are removed. Attachments now exclusively link to Drive files — no more dual storage path.
• Remove dead upload fallback: The "general" purpose fallback in the upload controller is gone. Uploads now require an explicit workspaceId and a valid purpose (avatar or wiki), otherwise they're rejected.
• Flatten storage paths: The YYYY/MM date-based subdirectories in buildPath are removed. Files are stored directly under their scope directory.
• Backward compatibility: Legacy static routes (/storage/avatars/, /storage/uploads/, /uploads/) remain so existing files still resolve. A new /storage/:workspaceId/uploads/* route serves workspace-scoped uploads.

New storage structure

storage/
└── {workspaceId}/
    ├── files/
    │   ├── {userId}/{fileId}.ext
    │   └── groupfolders/{teamFolderId}/{fileId}.ext
    └── uploads/
        ├── avatars/{userId}/{fileId}.ext
        └── wiki/
            ├── {spaceId}/{fileId}.ext
            └── imports/{fileId}.ext

Changes

Backend

• uploads.controller.ts — Require workspaceId and purpose from form data, use {workspaceId}/uploads as storage category, remove general fallback
• files.service.ts — Use {workspaceId}/files category in uploadFileStream and copyFile
• restore.service.ts — Use {workspaceId}/uploads category for re-uploaded assets, remove attachment restore logic
• storage.ts — Remove YYYY/MM date directories from buildPath
• static.ts — Add /storage/:workspaceId/uploads/* route via reply.sendFile(), enable decorateReply on first registration
• attachments.controller.ts — Remove uploadAttachmentHandler and direct-upload storage delete
• attachments.service.ts — Remove uploadAttachmentStream, simplify download to use linked Drive file only
• attachments.routes.ts — Remove POST /workspaces/:wid/attachments route
• backup.service.ts — Remove attachment file export logic, drop attachments/ from ZIP parsing
• backup.controller.ts — Remove attachments/ prefix from ZIP entry extraction

Frontend

• uploads/api.ts — Add required workspaceId and optional spaceId to UploadInput, send in form data
• wiki-editor.tsx — Accept optional workspaceId and spaceId props, send in upload form data
• wiki-page-view.tsx — Accept and pass workspaceId to WikiEditor
• knowledge.tsx — Pass workspace.id to WikiPageView
• topbar.tsx — Pass workspaceId in avatar upload call with guard
• profile-settings.tsx — Resolve workspaceId from route params, pass in avatar upload call with guard
• backup-settings.tsx — Remove attachment count from restore summary, update include-files label

Shared

• attachment.ts — Remove CreateAttachmentSchema (no longer used)
• backup.ts — Remove attachments from RestoreSummary