Add project groups and CodeMirror editors

[aarlint]

Summary

Two enhancements to the Switchboard sidebar and viewer experience:

Project Groups (Folder Groups)

Adds collapsible named folder groups to the sidebar for organizing projects into logical categories.

• Drag-and-drop projects into/out of groups for effortless organization
• Inline rename via double-click on group headers
• Tree-line connectors give visual hierarchy between groups and their projects
• Collapse/expand groups to reduce sidebar clutter
• Persisted state — group membership, collapse state, and names survive restarts via global settings
• Search-aware — groups automatically flatten during search so no results are hidden
• Full morphdom integration — sidebar updates are efficient DOM patches, not full re-renders

CodeMirror Editors for Memory, Skills, and Agents Viewers

Replaces read-only textContent rendering with full CodeMirror editors in the Memory, Skills, and Agents viewers.

• Syntax highlighting and proper code editing matching the existing Plans viewer pattern
• Save, Copy Content, and Copy Path action buttons added to each viewer header
• Consistent UX across all file viewers — no more plain-text rendering for code files
• Fix: Replaces hardcoded .claude string checks with CLAUDE_DIRNAME constant derived from CLAUDE_DIR for correct behavior across environments

Test Plan

• Create, rename, and delete folder groups in the sidebar
• Drag projects into and out of groups; verify persistence after restart
• Collapse/expand groups; verify state persists
• Search while groups exist — verify all matching sessions appear (groups flatten)
• Open Memory, Skills, and Agents viewers — verify CodeMirror renders with syntax highlighting
• Use Save, Copy Content, and Copy Path buttons in each viewer
• Verify no regressions in Plans viewer or terminal behavior

🤖 Generated with Claude Code

[aarlint]

Hey @abasiri, I rebased and cleaned up the pull requests into one. I hope this helps with the merge.

[abasiri]

Thank you Aarlint, The design overall looks great. One thing I was thinking is if we should combine all the different tabs for the different files into a single one, instead of the Memory tab, just having one that has all the agent files. Claude was complaining that the file lookups were a bit fragile, so I'm going to review that piece in more detail.

[aarlint]

Yeah, I was thinking those should actually be accessible / viewable at the project level since many of them are project specific. In design it could have one global tab for skills/agents/memories that exist in the ~.claude/ and each project would/could have its own subset. Let me see if i can refactor a bit

[aarlint]

Superseded by #8 which adds the unified Config tab on top of these changes.