refactor(cli): registry in commands/__init__, dispatcher main() in __main__

Split the cli package's two responsibilities out of __init__:

  * commands/__init__.py now assembles the COMMANDS registry and
    NO_MIGRATION_COMMANDS from the per-command modules — the command
    surface lives entirely under commands/.
  * __main__.py now owns main() (dispatch + migration gate + exit-code
    mapping) alongside the runnable entry guard.

cli/__init__.py shrinks to a shim that re-exports main / COMMANDS /
NO_MIGRATION_COMMANDS, so bot_bottle.cli.main (repo-root cli.py entry)
and the tests' bot_bottle.cli.COMMANDS keep working unchanged. Verified
`python -m bot_bottle.cli` (runpy) and `cli.py` both dispatch; full unit
suite green (2243).

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

bot_bottle/cli/__main__.py

@@ -1,15 +1,65 @@
-"""Entry point for `python -m bot_bottle.cli`.
+"""Entry point + dispatcher for `python -m bot_bottle.cli`.
 
-`cli.py` at the repo root is the usual way in; this makes the package
-runnable too, so the CLI works from an installed copy where there is no
-`cli.py` on disk to point at.
+Maps `bot-bottle <command>` to its handler in the COMMANDS registry
+(`bot_bottle.cli.commands`), enforces the schema-migration gate, and
+translates handler exceptions into process exit codes. The repo-root
+`cli.py` is the usual way in; this makes the package runnable too, so the
+CLI works from an installed copy where there is no `cli.py` on disk.
 """
 
 from __future__ import annotations
 
 import sys
 
-from . import main
+from ..errors import MissingEnvVarError
+from ..log import Die, die, error
+from ..manifest import ManifestError
+from ..orchestrator.store.store_manager import StoreManager
+from .commands import COMMANDS, NO_MIGRATION_COMMANDS
+from .commands.help import cmd_help
+
+
+def main(argv: list[str] | None = None) -> int:
+    if argv is None:
+        argv = sys.argv[1:]
+    if not argv:
+        cmd_help()
+        return 2
+    command = argv[0]
+    rest = argv[1:]
+    if command in ("-h", "--help"):
+        cmd_help()
+        return 0
+    handler = COMMANDS.get(command)
+    if handler is None:
+        cmd_help()
+        die(f"unknown command: {command}")
+    mgr = StoreManager.instance()
+    if command not in NO_MIGRATION_COMMANDS and not mgr.is_migrated():
+        sys.stderr.write("bot-bottle: database schema is out of date\n")
+        sys.stderr.write("Migrate now? [y/N] ")
+        sys.stderr.flush()
+        try:
+            answer = sys.stdin.readline().strip().lower()
+        except EOFError:
+            answer = ""
+        if answer != "y":
+            error("migration required — re-run and confirm to migrate")
+            return 1
+        mgr.migrate()
+    try:
+        return handler(rest) or 0
+    except MissingEnvVarError as e:
+        error(str(e))
+        return 1
+    except ManifestError as e:
+        error(str(e))
+        return 1
+    except Die as e:
+        return e.code if isinstance(e.code, int) else 1
+    except KeyboardInterrupt:
+        return 130
+
 
 if __name__ == "__main__":
     sys.exit(main())