feat: add quick install script and packaging (#197)

Give bot-bottle a real distribution path so new users can install
without cloning the repo:

- pyproject.toml: full project metadata, a `bot-bottle` console-script
  entry point (bot_bottle.cli:main), and package-data for the runtime
  assets (Dockerfiles, egress entrypoint, netpool defaults, macos init).
  Still zero runtime pip dependencies.
- install.sh: POSIX, sudo-free, idempotent bootstrapper — checks Python
  >= 3.11, creates ~/.bot-bottle/{agents,bottles,contrib}, installs via
  pipx (pip --user fallback), then runs `bot-bottle doctor`.
- `bot-bottle doctor`: new store-free subcommand reporting Python
  version, backend availability (reuses is_backend_available rather than
  hardcoding Docker), and config-dir presence. Exits non-zero when a hard
  prerequisite is unmet.
- PRD prd-new-install-script and unit tests for doctor, the packaging
  contract, and the install script.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

bot_bottle/cli/commands/__init__.py

@@ -21,6 +21,7 @@ _HANDLERS: dict[str, str] = {
     "backend": "backend:cmd_backend",
     "cleanup": "cleanup:cmd_cleanup",
     "commit": "commit:cmd_commit",
+    "doctor": "doctor:cmd_doctor",
     "edit": "edit:cmd_edit",
     "help": "help:cmd_help",
     "init": "init:cmd_init",
@@ -53,6 +54,6 @@ COMMANDS = {name: _lazy(spec) for name, spec in _HANDLERS.items()}
 # gating it on the schema breaks preflight on a fresh CI runner where stdin
 # isn't a TTY and the migration prompt can't be answered. `help` and `login`
 # likewise never touch the store.
-NO_MIGRATION_COMMANDS = frozenset({"backend", "help", "login"})
+NO_MIGRATION_COMMANDS = frozenset({"backend", "doctor", "help", "login"})
 
 __all__ = ["COMMANDS", "NO_MIGRATION_COMMANDS"]

bot_bottle/cli/commands/doctor.py

@@ -0,0 +1,81 @@
+"""`doctor` CLI command — validate host prerequisites for running
+bot-bottle and report what's ready.
+
+Fails (non-zero exit) only on the two hard requirements: a new-enough
+Python and at least one usable backend. The config directory is a soft
+check — `install.sh` creates it, but a missing one only warrants a note,
+not a failure, since `start` provisions what it needs on first run.
+"""
+
+from __future__ import annotations
+
+import argparse
+import sys
+from pathlib import Path
+
+from ...backend import is_backend_available, known_backend_names
+from ..constants import PROG
+
+MIN_PYTHON = (3, 11)
+CONFIG_DIR = ".bot-bottle"
+
+
+def _ok(label: str, detail: str) -> None:
+    print(f"ok:   {label}: {detail}")
+
+
+def _warn(label: str, detail: str) -> None:
+    print(f"warn: {label}: {detail}")
+
+
+def _fail(label: str, detail: str) -> None:
+    print(f"fail: {label}: {detail}")
+
+
+def _check_python() -> bool:
+    v = sys.version_info
+    detail = f"{v.major}.{v.minor}.{v.micro}"
+    if (v.major, v.minor) >= MIN_PYTHON:
+        _ok("python", detail)
+        return True
+    _fail("python", f"{detail}; need {MIN_PYTHON[0]}.{MIN_PYTHON[1]} or newer")
+    return False
+
+
+def _check_backends() -> bool:
+    """At least one backend must be available on this host. Report each
+    known backend so the operator sees why a missing one is missing."""
+    available = []
+    for name in known_backend_names():
+        if is_backend_available(name):
+            available.append(name)
+    if available:
+        _ok("backend", f"available: {', '.join(available)}")
+        return True
+    _fail(
+        "backend",
+        "no backend available; install Apple Container (macOS), "
+        "Firecracker (Linux), or Docker",
+    )
+    return False
+
+
+def _check_config_dir() -> None:
+    config = Path.home() / CONFIG_DIR
+    if config.is_dir():
+        _ok("config", str(config))
+    else:
+        _warn("config", f"{config} does not exist yet (created on first use)")
+
+
+def cmd_doctor(argv: list[str]) -> int:
+    parser = argparse.ArgumentParser(
+        prog=f"{PROG} doctor",
+        description="Check host prerequisites for running bot-bottle.",
+    )
+    parser.parse_args(argv)
+
+    # Hard requirements gate the exit code; the config note is advisory.
+    required = [_check_python(), _check_backends()]
+    _check_config_dir()
+    return 0 if all(required) else 1

bot_bottle/cli/commands/help.py

@@ -25,6 +25,7 @@ def cmd_help(argv: list[str] | None = None) -> int:
     w("  backend   set up / check / undo a backend's host prerequisites (setup|status|teardown)\n")
     w("  cleanup   stop and remove all active bot-bottle containers\n")
     w("  commit    snapshot a running bottle's container state to a Docker image\n")
+    w("  doctor    check host prerequisites (Python, backend, config dir)\n")
     w("  edit      open an agent in vim for editing\n")
     w("  help      show this command list\n")
     w("  init      interactively create a new agent and add it to bot-bottle.json\n")