shell: fish functions -> ~/.local/bin executables + bash/zsh ports; manage ~/.agents

- 16 cross-shell utilities converted to sh/bash chezmoi executables:
  ai c2p cp-appid extract_agents fab gdc gh-sonr-org-migrate ghg-clone
  ghn gho git-summary launch_omp_livediff_overlay lc-elir mdcp mdp pj
  (ghg-clone not named ghg: unrelated cargo binary owns that name)
- cwd/history helpers stay per-shell: yy c cd clip-last + ghg/ghn/gho
  cd-wrappers in bash/functions/ and zsh/functions/, loaded by rc files
- fish keeps only shell-state functions; converted ones now hit PATH
- cp-appid ignore gating moved to .local/bin path
- dot_agents/skills: 82 skills materialized from dotstate storage so
  dot_claude skill symlinks resolve on fresh bootstrap; dotstate
  profile/symlinks.json released .agents/skills .bashrc .zshrc

dot_local/bin/executable_ai

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Choose and launch an AI CLI via gum.
+choice=$(gum choose --header 'AI CLI' claude opencode codex hermes fractal) || exit 0
+[ -n "$choice" ] || exit 0
+
+case "$choice" in
+    claude) exec claude --dangerously-skip-permissions ;;
+    # labels match the binary names, so just run it;
+    # add a dedicated case here if another tool needs flags
+    *) exec "$choice" ;;
+esac