feat: session state persistence — tmux-state.json manifest (#512)

Implement tmux-state.sh: snapshots all tmux pane state to ~/.timmy/tmux-state.json
and ~/.hermes/tmux-state.json every supervisor cycle.

Per-pane tracking:
- address, pane_id, pid, size, active state
- command, title, tty
- hermes profile, model, provider
- session_id (for --resume)
- task (last prompt extracted from pane content)
- context_pct (estimated from pane content)

Also implement tmux-resume.sh: cold-start reads manifest and respawns
hermes sessions with --resume using saved session IDs.

Closes #512

bin/tmux-resume.sh

@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+# ── tmux-resume.sh — Cold-start Session Resume ───────────────────────────
+# Reads ~/.timmy/tmux-state.json and resumes hermes sessions.
+# Run at startup to restore pane state after supervisor restart.
+# ──────────────────────────────────────────────────────────────────────────
+
+set -euo pipefail
+
+MANIFEST="${HOME}/.timmy/tmux-state.json"
+
+if [ ! -f "$MANIFEST" ]; then
+    echo "[tmux-resume] No manifest found at $MANIFEST — starting fresh."
+    exit 0
+fi
+
+python3 << 'PYEOF'
+import json, subprocess, os, sys
+from datetime import datetime, timezone
+
+MANIFEST = os.path.expanduser("~/.timmy/tmux-state.json")
+
+def run(cmd):
+    try:
+        r = subprocess.run(cmd, shell=True, capture_output=True, text=True, timeout=30)
+        return r.stdout.strip(), r.returncode
+    except Exception as e:
+        return str(e), 1
+
+def session_exists(name):
+    out, _ = run(f"tmux has-session -t '{name}' 2>&1")
+    return "can't find" not in out.lower()
+
+with open(MANIFEST) as f:
+    state = json.load(f)
+
+ts = state.get("timestamp", "unknown")
+age = "unknown"
+try:
+    t = datetime.fromisoformat(ts.replace("Z", "+00:00"))
+    delta = datetime.now(timezone.utc) - t
+    mins = int(delta.total_seconds() / 60)
+    if mins < 60:
+        age = f"{mins}m ago"
+    else:
+        age = f"{mins//60}h {mins%60}m ago"
+except:
+    pass
+
+print(f"[tmux-resume] Manifest from {age}: {state['summary']['total_sessions']} sessions, "
+      f"{state['summary']['hermes_panes']} hermes panes")
+
+restored = 0
+skipped = 0
+
+for pane in state.get("panes", []):
+    if not pane.get("is_hermes"):
+        continue
+
+    addr = pane["address"]  # e.g. "BURN:2.3"
+    session = addr.split(":")[0]
+    session_id = pane.get("session_id")
+    profile = pane.get("profile", "default")
+    model = pane.get("model", "")
+    task = pane.get("task", "")
+
+    # Skip if session already exists (already running)
+    if session_exists(session):
+        print(f"  [skip] {addr} — session '{session}' already exists")
+        skipped += 1
+        continue
+
+    # Respawn hermes with session resume if we have a session ID
+    if session_id:
+        print(f"  [resume] {addr} — profile={profile} model={model} session={session_id}")
+        cmd = f"hermes chat --resume {session_id}"
+    else:
+        print(f"  [start]  {addr} — profile={profile} model={model} (no session ID)")
+        cmd = f"hermes chat --profile {profile}"
+
+    # Create tmux session and run hermes
+    run(f"tmux new-session -d -s '{session}' -n '{session}:0'")
+    run(f"tmux send-keys -t '{session}' '{cmd}' Enter")
+    restored += 1
+
+# Write resume log
+log = {
+    "resumed_at": datetime.now(timezone.utc).isoformat(),
+    "manifest_age": age,
+    "restored": restored,
+    "skipped": skipped,
+}
+log_path = os.path.expanduser("~/.timmy/tmux-resume.log")
+with open(log_path, "w") as f:
+    json.dump(log, f, indent=2)
+
+print(f"[tmux-resume] Done: {restored} restored, {skipped} skipped")
+PYEOF

bin/tmux-state.sh

@@ -0,0 +1,237 @@
+#!/usr/bin/env bash
+# ── tmux-state.sh — Session State Persistence Manifest ───────────────────
+# Snapshots all tmux pane state to ~/.timmy/tmux-state.json
+# Run every supervisor cycle. Cold-start reads this manifest to resume.
+# ──────────────────────────────────────────────────────────────────────────
+
+set -euo pipefail
+
+MANIFEST="${HOME}/.timmy/tmux-state.json"
+mkdir -p "$(dirname "$MANIFEST")"
+
+python3 << 'PYEOF'
+import json, subprocess, os, time, re, sys
+from datetime import datetime, timezone
+from pathlib import Path
+
+MANIFEST = os.path.expanduser("~/.timmy/tmux-state.json")
+
+def run(cmd):
+    """Run command, return stdout or empty string."""
+    try:
+        r = subprocess.run(cmd, shell=True, capture_output=True, text=True, timeout=5)
+        return r.stdout.strip()
+    except Exception:
+        return ""
+
+def get_sessions():
+    """Get all tmux sessions with metadata."""
+    raw = run("tmux list-sessions -F '#{session_name}|#{session_windows}|#{session_created}|#{session_attached}|#{session_group}|#{session_id}'")
+    sessions = []
+    for line in raw.splitlines():
+        if not line.strip():
+            continue
+        parts = line.split("|")
+        if len(parts) < 6:
+            continue
+        sessions.append({
+            "name": parts[0],
+            "windows": int(parts[1]),
+            "created_epoch": int(parts[2]),
+            "created": datetime.fromtimestamp(int(parts[2]), tz=timezone.utc).isoformat(),
+            "attached": parts[3] == "1",
+            "group": parts[4],
+            "id": parts[5],
+        })
+    return sessions
+
+def get_panes():
+    """Get all tmux panes with full metadata."""
+    fmt = '#{session_name}|#{window_index}|#{pane_index}|#{pane_pid}|#{pane_title}|#{pane_width}x#{pane_height}|#{pane_active}|#{pane_current_command}|#{pane_start_command}|#{pane_tty}|#{pane_id}|#{window_name}|#{session_id}'
+    raw = run(f"tmux list-panes -a -F '{fmt}'")
+    panes = []
+    for line in raw.splitlines():
+        if not line.strip():
+            continue
+        parts = line.split("|")
+        if len(parts) < 13:
+            continue
+        session, win, pane, pid, title, size, active, cmd, start_cmd, tty, pane_id, win_name, sess_id = parts[:13]
+        w, h = size.split("x") if "x" in size else ("0", "0")
+        panes.append({
+            "session": session,
+            "window_index": int(win),
+            "window_name": win_name,
+            "pane_index": int(pane),
+            "pane_id": pane_id,
+            "pid": int(pid) if pid.isdigit() else 0,
+            "title": title,
+            "width": int(w),
+            "height": int(h),
+            "active": active == "1",
+            "command": cmd,
+            "start_command": start_cmd,
+            "tty": tty,
+            "session_id": sess_id,
+        })
+    return panes
+
+def extract_hermes_state(pane):
+    """Try to extract hermes session info from a pane."""
+    info = {
+        "is_hermes": False,
+        "profile": None,
+        "model": None,
+        "provider": None,
+        "session_id": None,
+        "task": None,
+    }
+    title = pane.get("title", "")
+    cmd = pane.get("command", "")
+    start = pane.get("start_command", "")
+
+    # Detect hermes processes
+    is_hermes = any(k in (title + " " + cmd + " " + start).lower()
+                    for k in ["hermes", "timmy", "mimo", "claude", "gpt"])
+    if not is_hermes and cmd not in ("python3", "python3.11", "bash", "zsh", "fish"):
+        return info
+
+    # Try reading pane content for model/provider clues
+    pane_content = run(f"tmux capture-pane -t '{pane['session']}:{pane['window_index']}.{pane['pane_index']}' -p -S -20 2>/dev/null")
+
+    # Extract model from pane content patterns
+    model_patterns = [
+        r"(?:mimo-v2-pro|claude-[\w.-]+|gpt-[\w.-]+|gemini-[\w.-]+|qwen[\w:.-]*)",
+    ]
+    for pat in model_patterns:
+        m = re.search(pat, pane_content, re.IGNORECASE)
+        if m:
+            info["model"] = m.group(0)
+            info["is_hermes"] = True
+            break
+
+    # Provider inference from model
+    model = (info["model"] or "").lower()
+    if "mimo" in model:
+        info["provider"] = "nous"
+    elif "claude" in model:
+        info["provider"] = "anthropic"
+    elif "gpt" in model:
+        info["provider"] = "openai"
+    elif "gemini" in model:
+        info["provider"] = "google"
+    elif "qwen" in model:
+        info["provider"] = "custom"
+
+    # Profile from session name
+    session = pane["session"].lower()
+    if "burn" in session:
+        info["profile"] = "burn"
+    elif session in ("dev", "0"):
+        info["profile"] = "default"
+    else:
+        info["profile"] = session
+
+    # Try to extract session ID (hermes uses UUIDs)
+    uuid_match = re.findall(r'[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}', pane_content)
+    if uuid_match:
+        info["session_id"] = uuid_match[-1]  # most recent
+        info["is_hermes"] = True
+
+    # Last prompt — grab the last user-like line
+    lines = pane_content.splitlines()
+    for line in reversed(lines):
+        stripped = line.strip()
+        if stripped and not stripped.startswith(("─", "│", "╭", "╰", "▸", "●", "○")) and len(stripped) > 10:
+            info["task"] = stripped[:200]
+            break
+
+    return info
+
+def get_context_percent(pane):
+    """Estimate context usage from pane content heuristics."""
+    content = run(f"tmux capture-pane -t '{pane['session']}:{pane['window_index']}.{pane['pane_index']}' -p -S -5 2>/dev/null")
+    # Look for context indicators like "ctx 45%" or "[░░░░░░░░░░]"
+    ctx_match = re.search(r'ctx\s*(\d+)%', content)
+    if ctx_match:
+        return int(ctx_match.group(1))
+    bar_match = re.search(r'\[(░+█*█*░*)\]', content)
+    if bar_match:
+        bar = bar_match.group(1)
+        filled = bar.count('█')
+        total = len(bar)
+        if total > 0:
+            return int((filled / total) * 100)
+    return None
+
+def build_manifest():
+    """Build the full tmux state manifest."""
+    now = datetime.now(timezone.utc)
+    sessions = get_sessions()
+    panes = get_panes()
+
+    pane_manifests = []
+    for p in panes:
+        hermes = extract_hermes_state(p)
+        ctx = get_context_percent(p)
+
+        entry = {
+            "address": f"{p['session']}:{p['window_index']}.{p['pane_index']}",
+            "pane_id": p["pane_id"],
+            "pid": p["pid"],
+            "size": f"{p['width']}x{p['height']}",
+            "active": p["active"],
+            "command": p["command"],
+            "title": p["title"],
+            "profile": hermes["profile"],
+            "model": hermes["model"],
+            "provider": hermes["provider"],
+            "session_id": hermes["session_id"],
+            "task": hermes["task"],
+            "context_pct": ctx,
+            "is_hermes": hermes["is_hermes"],
+        }
+        pane_manifests.append(entry)
+
+    # Active pane summary
+    active_panes = [p for p in pane_manifests if p["active"]]
+    primary = active_panes[0] if active_panes else {}
+
+    manifest = {
+        "version": 1,
+        "timestamp": now.isoformat(),
+        "timestamp_epoch": int(now.timestamp()),
+        "hostname": os.uname().nodename,
+        "sessions": sessions,
+        "panes": pane_manifests,
+        "summary": {
+            "total_sessions": len(sessions),
+            "total_panes": len(pane_manifests),
+            "hermes_panes": sum(1 for p in pane_manifests if p["is_hermes"]),
+            "active_pane": primary.get("address"),
+            "active_model": primary.get("model"),
+            "active_provider": primary.get("provider"),
+        },
+    }
+
+    return manifest
+
+# --- Main ---
+manifest = build_manifest()
+
+# Write manifest
+with open(MANIFEST, "w") as f:
+    json.dump(manifest, f, indent=2)
+
+# Also write to ~/.hermes/tmux-state.json for compatibility
+hermes_manifest = os.path.expanduser("~/.hermes/tmux-state.json")
+os.makedirs(os.path.dirname(hermes_manifest), exist_ok=True)
+with open(hermes_manifest, "w") as f:
+    json.dump(manifest, f, indent=2)
+
+print(f"[tmux-state] {manifest['summary']['total_panes']} panes, "
+      f"{manifest['summary']['hermes_panes']} hermes, "
+      f"active={manifest['summary']['active_pane']} "
+      f"@ {manifest['summary']['active_model']}")
+print(f"[tmux-state] written to {MANIFEST}")
+PYEOF