feat(skills): skill lifecycle + ms-* skill set completion (#40, #41, #42)

- scripts/skill.sh: install (bundled or path) / activate / deactivate /
  uninstall (refuses while enabled) / list
- skills-enabled + skills-available dirs under the data root; a skill not
  in skills-enabled is not enabled or available for use
- pi adapter: MOSAIC_SKILLS -> --skill per dir; --no-skills when none
- agent.sh: seat definitions declare skills[]; resolution against
  skills-enabled refuses the launch loudly when missing
- ms-* skills completed (owner-authored canon, hands-off): ms-tools
  adapted to the runtime, ms-file-read/write/agent/conductor bodies
  written in the owner's style; ms-agent-watch + ms-unslop untouched
- tasks/USER.md onboarding fixtures; suite hardening (nested def path,
  user seed, mock-adapter dispatch evidence)

Suites: config 24, task 74, release 14, conductor 17, verify PASS.
RELEASE 0.0.12 packaged; health-gated activation on merge.

Closes #40, closes #41, closes #42

tools/tmux/auto-submit-drafts.sh

@@ -0,0 +1,80 @@
+#!/usr/bin/env bash
+# auto-submit-drafts.sh — watchdog for Claude Code panes that receive channel
+# messages but leave them as unsubmitted prompt drafts. Intended for Mos only.
+set -uo pipefail
+
+TARGET="${1:-mos-claude}"
+INTERVAL="${INTERVAL:-2}"
+STABLE_SECONDS="${STABLE_SECONDS:-4}"
+LOG_PREFIX="[auto-submit-drafts:$TARGET]"
+
+last_prompt=""
+first_seen=0
+
+prompt_text() {
+  tmux capture-pane -t "$TARGET" -p 2>/dev/null | python3 -c '
+import sys, re
+lines = sys.stdin.read().splitlines()
+idx = None
+for i in range(len(lines)-1, -1, -1):
+    if "❯" in lines[i]:
+        idx = i
+        break
+if idx is None:
+    raise SystemExit
+parts = []
+after = lines[idx].split("❯", 1)[1]
+parts.append(after)
+for line in lines[idx+1:]:
+    # Stop at Claude Code separator/border lines.
+    if "─" in line or "╰" in line or "╭" in line:
+        break
+    s = line.replace("\u00a0", " ")
+    s = re.sub(r"[\x00-\x1f\x7f]", "", s).strip()
+    if s:
+        parts.append(s)
+text = " ".join(parts).replace("\u00a0", " ")
+text = re.sub(r"[\x00-\x1f\x7f]", "", text).strip()
+print(text)
+'
+}
+
+while true; do
+  if ! tmux has-session -t "$TARGET" 2>/dev/null; then
+    echo "$LOG_PREFIX target missing; waiting" >&2
+    sleep "$INTERVAL"
+    last_prompt=""
+    first_seen=0
+    continue
+  fi
+
+  current="$(prompt_text || true)"
+  now="$(date +%s)"
+
+  if [[ -z "$current" ]]; then
+    last_prompt=""
+    first_seen=0
+    sleep "$INTERVAL"
+    continue
+  fi
+
+  if [[ "$current" != "$last_prompt" ]]; then
+    last_prompt="$current"
+    first_seen="$now"
+    sleep "$INTERVAL"
+    continue
+  fi
+
+  age=$(( now - first_seen ))
+  if (( age >= STABLE_SECONDS )); then
+    echo "$LOG_PREFIX submitting stable draft after ${age}s: ${current:0:120}" >&2
+    tmux send-keys -t "$TARGET" C-j
+    sleep 0.8
+    tmux send-keys -t "$TARGET" C-m
+    sleep 2
+    last_prompt=""
+    first_seen=0
+  else
+    sleep "$INTERVAL"
+  fi
+done