refactor(store): consolidate the SQLite store family into bot_bottle.store

Move the DbStore base (db_store), the shared schema-migration base (migrations /
TableMigrations), the concrete stores (audit_store, config_store, queue_store),
and StoreManager out of the package root into a bot_bottle/store/ package, so
persistence lives in one place rather than scattered across the root.

Callers use direct submodule imports (from bot_bottle.store.store_manager
import StoreManager). Inside the moved modules the relative imports point back
up to their non-store siblings (..paths, ..supervise_types) while co-moved
siblings stay package-local; the flat-import fallbacks are untouched. The
orchestrator's own stores (config_store, secret_store, registry) stay in
orchestrator/ and repoint to the moved DbStore / TableMigrations.

No behavior change; full unit suite green.

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

bot_bottle/store/store_manager.py

@@ -0,0 +1,61 @@
+"""Singleton manager for all bot-bottle SQLite stores (PRD 0013)."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+try:
+    from .audit_store import AuditStore
+    from .config_store import ConfigStore
+    from .queue_store import QueueStore
+except ImportError:
+    from audit_store import AuditStore  # type: ignore[import-not-found]  # pylint: disable=import-error,no-name-in-module
+    from config_store import ConfigStore  # type: ignore[import-not-found]  # pylint: disable=import-error,no-name-in-module
+    from queue_store import QueueStore  # type: ignore[import-not-found]  # pylint: disable=import-error,no-name-in-module
+
+_instance: StoreManager | None = None
+
+
+class StoreManager:
+    """Owns db_path and delegates migrate/is_migrated across all stores.
+
+    Use instance() for normal access. Call reset(db_path) in tests to swap
+    the singleton to a temp path, then reset() with no args to restore the
+    default."""
+
+    def __init__(self, db_path: Path | None = None) -> None:
+        if db_path is None:
+            try:
+                from ..paths import host_db_path
+            except ImportError:
+                from paths import host_db_path  # type: ignore[import-not-found]  # pylint: disable=import-error,no-name-in-module
+            db_path = host_db_path()
+        self.db_path = db_path
+
+    @classmethod
+    def instance(cls) -> StoreManager:
+        global _instance
+        if _instance is None:
+            _instance = cls()
+        return _instance
+
+    @classmethod
+    def reset(cls, db_path: Path | None = None) -> None:
+        """Replace the singleton. Pass db_path for test isolation; omit to restore default."""
+        global _instance
+        _instance = cls(db_path)
+
+    def is_migrated(self) -> bool:
+        return (
+            QueueStore("", self.db_path).is_migrated()
+            and AuditStore(self.db_path).is_migrated()
+            and ConfigStore(self.db_path).is_migrated()
+        )
+
+    def migrate(self) -> None:
+        QueueStore("", self.db_path).migrate()
+        AuditStore(self.db_path).migrate()
+        ConfigStore(self.db_path).migrate()
+
+
+__all__ = ["StoreManager"]