docs: update ROADMAP for v2.6.0 planned scope

Add tag exclusion UI, untagged filter, quick tagging, and bulk
operations to v2.6.0. Move improved search syntax to wishlist.
Add tag merging, aliases, icons, hidden tags, and keyboard
shortcuts to Ideas/Wishlist.

Author: fmaass

ROADMAP.md

@@ -149,6 +149,9 @@ See [release notes](https://github.com/fmaass/teedy-docs/releases/tag/v2.5.0) fo
 - Tag tree always visible alongside documents, with facet-driven counts and auto-expand to active branches
 - Document slide-over panel (side peek) to preview documents without leaving the list
 - AND/OR toggle for tag intersection vs union mode
+- Tag exclusion UI: tri-state per tag (neutral / included / excluded) with visual differentiation on chips; backend `!tag:` / `search[nottag]` already supports this
+- Untagged document filter: "Untagged" pseudo-node or toggle to surface documents with zero tags
+- Quick tagging from document list: right-click context menu with tag picker to add/remove tags without opening the edit form
 - Replaces the separate Documents and Browse navigation items with a single "Documents" view
 
 ### Login brute force protection
@@ -181,25 +184,32 @@ See [release notes](https://github.com/fmaass/teedy-docs/releases/tag/v2.5.0) fo
 - Enforce mixed-case + digit or zxcvbn-based strength check
 - Reject passwords matching the username
 
+### Bulk operations
+
+- Multi-select in the document list (PrimeVue DataTable `selectionMode="multiple"`) with select-all
+- Bulk add tags, remove tags, delete (to trash), and set language via floating toolbar or context menu
+- `POST /document/bulk` endpoint to batch operations without N individual API calls
+- Natural extension of the quick-tagging context menu in the unified view
+
 ### Folder ingestion
 
 - Watch a filesystem directory for new files and auto-import as documents
 - Configurable polling interval, post-processing (delete or move), error handling
 
-### Improved search syntax
-
-- Expose Lucene's query capabilities in the UI (AND/OR/NOT operators, date ranges, field-specific queries)
-- Search syntax help/documentation in the UI
-
 ---
 
 ## Ideas / Wishlist
 
 Lower-priority ideas that may be worth exploring:
 
+- **Tag merging**: consolidate duplicate or similar tags into one, reassigning all document links
+- **Tag aliases**: multiple search names per tag (e.g., "Invoice" also matches "Rechnung") for search and auto-tag matching
+- **Tag icons**: optional emoji or icon per tag for visual scanability beyond color dots
+- **Hidden tags**: flag to hide infrequently-used tags from the tree with a "show hidden" toggle
+- **Keyboard shortcuts for tags**: shortcuts for AND/OR toggle, tag focus, and hotkey tagging (assign 1-9 to favorite tags)
+- **Improved search syntax**: expose Lucene operators in UI (AND/OR/NOT, date ranges, field-specific queries) with syntax help popover
 - **S3-compatible storage backend**: store files in object storage instead of local filesystem
 - **Admin-only tag management** (upstream [sismics/docs#323](https://github.com/sismics/docs/issues/323)): RBAC for tag creation
-- **Bulk operations UI**: select multiple documents for tagging, moving, or deleting
 - **Document templates**: pre-filled metadata for common document types
 - **Webhook / event system enhancements**: document lifecycle events for external automation
 - **Improved email integration** (upstream [sismics/docs#352](https://github.com/sismics/docs/issues/352)): IMAP monitoring, attachment extraction