Per-title KG switching for publishing pipeline

[AlexMikhalev]

Parent

Epic: #43

Problem

The terraphim KG is global (~/.config/terraphim/kg/). When working on multiple book titles, KG entries from one title should not interfere with another. Need a mechanism to activate/deactivate per-title entries.

Proposed Solution

Script: publishing/scripts/switch-title.sh <slug>

Directory Structure

~/.config/terraphim/kg/
  bun.md                          # global (always active)
  bun_install.md                  # global
  Terraphim AI.md                 # global
  publishing/                     # publishing-specific
    context-graphs-for-engineers/
      context graph.md
      decision trace.md
      ...
    title-2-slug/
      ...
  .active-title                   # marker: current slug

switch-title.sh Behavior

1. Read current active title from ~/.config/terraphim/kg/.active-title
2. If different from requested slug:
   • Remove symlinks from previous title's entries in the KG root
   • Create symlinks for new title's entries: kg/publishing/<slug>/*.md -> kg/
   • Update .active-title marker file
3. Rebuild Aho-Corasick automata: terraphim-agent graph --role "Publishing Editor"
4. Report: "Switched from to , N entries activated"

Alternative (simpler)

Instead of symlinks, the role config (#45) already points to kg/publishing/. If terraphim-agent scans subdirectories recursively, no switching is needed -- just update .active-title for the ${ACTIVE_TITLE_DIR} haystack substitution.

Need to verify: does terraphim-agent scan kg/publishing/ recursively or only the root?

Dependencies

• Publishing Editor role (Create Publishing Editor terraphim role for domain model search #45) uses ${ACTIVE_TITLE_DIR} from .active-title
• derive-kg-entries.py writes to kg/publishing/<slug>/