Migrate best practices to skynet/best-practices repo

Remove all best-practices topic files and .distill-state.json from
claude-foundations. BESTPRACTICES.md now redirects to the standalone
repo at ~/dev/claude/projects/best-practices/. Remove the now-unnecessary
sync-best-practices.sh script.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -1,6 +1,6 @@
 # claude-foundations
 
-Shared infrastructure for Claude Code sessions: hooks, formatters, best practices, and the knowledge distillation pipeline.
+Shared infrastructure for Claude Code sessions: hooks, formatters, and the knowledge distillation pipeline.
 
 ## Repository Structure
 
@@ -25,11 +25,10 @@ claude-foundations/
     setup-formatters.sh    # Set up formatters for a project
     statusline.sh          # Status line renderer (symlinked from ~/.claude/status/)
     set-topic.sh           # Set per-session topic for the status line
-  best-practices/          # Generalised best practices (one file per topic) — also maintained in skynet/best-practices
   context/                 # Active work focus detail files
   memory/                  # Session logs and reflections
   settings.yaml            # Knowledge pipeline configuration
-  BESTPRACTICES.md         # Best practices index (loaded by context-load)
+  BESTPRACTICES.md         # Redirect to skynet/best-practices repo
   CLAUDE.md                # Global project guidelines (symlinked to ~/dev/claude/)
   CONTEXT.md               # Active work focus index (loaded by context-load)
   HOOKS.md                 # Hook documentation