Initial import: shopdb-flask multi-site asset platform

Flask + Vue rewrite of the classic-ASP shopdb, built as a plugin
framework so sister GE Aerospace sites can adopt it. Product version
0.7.0-pre-0.8.0, plugin contract 0.11.0, 966 backend tests.

Key entry points:
- docs/INSTALL-WINDOWS-IIS.md - tested Windows + IIS install runbook
  (own-site and subpath deployment methods)
- docs/PILOT-DEPLOY.md - production pilot: stand up + import + verify
- docs/IMPORT-API.md - schema-agnostic legacy data import contract
- scripts/site_imports/wjf/ - West Jefferson reference import loader
- docs/adr/ - twelve accepted architecture decision records

migrations/versions/7d24_customfield_searchable.py

@@ -0,0 +1,50 @@
+"""Custom field searchable flag (customfields.searchable)
+
+Adds a boolean customfields.searchable column (default false). When true, the
+field's stored values are matched by global search and a hit routes to the
+owning asset's detail page.
+
+Idempotent guard so it is safe on a partially-migrated box; real downgrade.
+
+Revision ID: 7d24_customfield_searchable
+Revises: 7d23_user_mustchangepassword
+Create Date: 2026-07-12
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = '7d24_customfield_searchable'
+down_revision = '7d23_user_mustchangepassword'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    bind = op.get_bind()
+    insp = sa.inspect(bind)
+
+    if 'customfields' not in insp.get_table_names():
+        return
+    columns = {c['name'] for c in insp.get_columns('customfields')}
+    if 'searchable' in columns:
+        return
+
+    op.add_column(
+        'customfields',
+        sa.Column('searchable', sa.Boolean(),
+                  nullable=False, server_default=sa.false()))
+
+
+def downgrade():
+    bind = op.get_bind()
+    insp = sa.inspect(bind)
+
+    if 'customfields' not in insp.get_table_names():
+        return
+    columns = {c['name'] for c in insp.get_columns('customfields')}
+    if 'searchable' not in columns:
+        return
+
+    op.drop_column('customfields', 'searchable')