fix(app): Normalize provisioning templates and Clerk props

Use autoescape for Jinja rendering to satisfy bandit checks and\nremove deprecated Clerk SignInButton props to restore type checks.\nAlso ignore tsbuildinfo artifacts and tidy boot instructions.\n\nCo-Authored-By: Claude <noreply@anthropic.com>

backend/alembic/versions/e4f5a6b7c8d9_make_agent_last_seen_nullable.py

@@ -0,0 +1,27 @@
+"""make agent last_seen_at nullable
+
+Revision ID: e4f5a6b7c8d9
+Revises: d3e4f5a6b7c8
+Create Date: 2026-02-04 07:10:00.000000
+
+"""
+
+from __future__ import annotations
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = "e4f5a6b7c8d9"
+down_revision = "d3e4f5a6b7c8"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.alter_column("agents", "last_seen_at", existing_type=sa.DateTime(), nullable=True)
+
+
+def downgrade() -> None:
+    op.alter_column("agents", "last_seen_at", existing_type=sa.DateTime(), nullable=False)