chore: restore .claude commands, agents, helpers & skills (lost in 1df208d)

Restores the entire .claude/ infrastructure that was accidentally deleted
in commit 1df208d ('feat(timeline): add pulse animation for in-flight drag
mutations'). Recovered via git checkout 1df208d^.

Restored:
- .claude/commands/ (gitlooper, sparc/, github/, automation/, monitoring/,
  optimization/, hooks/, plan, implement, research, review, perf, visualaudit)
- .claude/agents/ (core/, github/, sparc/, v3/, swarm/, templates/, ...)
- .claude/helpers/ (41 scripts incl. hook-handler.cjs, statusline.cjs)
- .claude/skills/ (20 skills incl. sparc-methodology, github-*, v3-*)
- .claude/settings.json (hooks configuration)

Also updated all CapaKraken → Nexus references in affected command files.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/helpers/statusline-hook.sh

@@ -0,0 +1,21 @@
+# Claude Flow V3 Statusline Hook
+# Add to your shell RC file (.bashrc, .zshrc, etc.)
+
+# Function to get statusline
+claude_flow_statusline() {
+  local statusline_script="${CLAUDE_FLOW_DIR:-.claude}/helpers/statusline.cjs"
+  if [ -f "$statusline_script" ]; then
+    node "$statusline_script" 2>/dev/null || echo ""
+  fi
+}
+
+# For bash PS1
+# export PS1='$(claude_flow_statusline) \n\$ '
+
+# For zsh RPROMPT
+# export RPROMPT='$(claude_flow_statusline)'
+
+# For starship (add to starship.toml)
+# [custom.claude_flow]
+# command = "node .claude/helpers/statusline.cjs 2>/dev/null"
+# when = "test -f .claude/helpers/statusline.cjs"