feat(morrowind): add Perception/Command protocol + SQLite command log (#859, #855)

Implement two foundational infrastructure pieces for the Morrowind integration:

1. Perception/Command Protocol (Issue #859):
   - Formal spec document with JSON schemas, API contracts, versioning strategy
   - Engine-agnostic design following the Falsework Rule
   - Pydantic v2 models (PerceptionOutput, CommandInput) for runtime validation

2. SQLite Command Log + Training Pipeline (Issue #855):
   - SQLAlchemy model for command_log table with full indexing
   - CommandLogger class with log_command(), query(), export_training_data()
   - TrainingExporter with chat-completion, episode, and instruction formats
   - Storage management (rotation/archival) utilities
   - Alembic migration for the new table

Includes 39 passing tests covering schema validation, logging, querying, and export.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

migrations/versions/a1b2c3d4e5f6_create_command_log_table.py

@@ -0,0 +1,89 @@
+"""Create command_log table
+
+Revision ID: a1b2c3d4e5f6
+Revises: 0093c15b4bbf
+Create Date: 2026-03-21 12:00:00.000000
+
+"""
+
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision: str = "a1b2c3d4e5f6"
+down_revision: Union[str, Sequence[str], None] = "0093c15b4bbf"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    op.create_table(
+        "command_log",
+        sa.Column("id", sa.Integer(), autoincrement=True, nullable=False),
+        sa.Column("timestamp", sa.DateTime(), nullable=False),
+        sa.Column("command", sa.String(length=64), nullable=False),
+        sa.Column("params", sa.Text(), nullable=False, server_default="{}"),
+        sa.Column("reasoning", sa.Text(), nullable=False, server_default=""),
+        sa.Column(
+            "perception_snapshot", sa.Text(), nullable=False, server_default="{}"
+        ),
+        sa.Column("outcome", sa.Text(), nullable=True),
+        sa.Column(
+            "agent_id",
+            sa.String(length=64),
+            nullable=False,
+            server_default="timmy",
+        ),
+        sa.Column("episode_id", sa.String(length=128), nullable=True),
+        sa.Column("cell", sa.String(length=255), nullable=True),
+        sa.Column(
+            "protocol_version",
+            sa.String(length=16),
+            nullable=False,
+            server_default="1.0.0",
+        ),
+        sa.Column("created_at", sa.DateTime(), nullable=False),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index(
+        op.f("ix_command_log_timestamp"), "command_log", ["timestamp"], unique=False
+    )
+    op.create_index(
+        op.f("ix_command_log_command"), "command_log", ["command"], unique=False
+    )
+    op.create_index(
+        op.f("ix_command_log_agent_id"), "command_log", ["agent_id"], unique=False
+    )
+    op.create_index(
+        op.f("ix_command_log_episode_id"),
+        "command_log",
+        ["episode_id"],
+        unique=False,
+    )
+    op.create_index(
+        op.f("ix_command_log_cell"), "command_log", ["cell"], unique=False
+    )
+    op.create_index(
+        "ix_command_log_cmd_cell", "command_log", ["command", "cell"], unique=False
+    )
+    op.create_index(
+        "ix_command_log_episode",
+        "command_log",
+        ["episode_id", "timestamp"],
+        unique=False,
+    )
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    op.drop_index("ix_command_log_episode", table_name="command_log")
+    op.drop_index("ix_command_log_cmd_cell", table_name="command_log")
+    op.drop_index(op.f("ix_command_log_cell"), table_name="command_log")
+    op.drop_index(op.f("ix_command_log_episode_id"), table_name="command_log")
+    op.drop_index(op.f("ix_command_log_agent_id"), table_name="command_log")
+    op.drop_index(op.f("ix_command_log_command"), table_name="command_log")
+    op.drop_index(op.f("ix_command_log_timestamp"), table_name="command_log")
+    op.drop_table("command_log")