feat: production release with React SPA, file attachments, and deploy tooling

Backend:
- Add file_handlers.go: presigned upload/download for item attachments
- Add item_files.go: item file and thumbnail DB operations
- Add migration 011: item_files table and thumbnail_key column
- Update items/projects/relationships DB with extended field support
- Update routes: React SPA serving from web/dist, file upload endpoints
- Update auth handlers and middleware for cookie + bearer token auth
- Remove Go HTML templates (replaced by React SPA)
- Update storage client for presigned URL generation

Frontend:
- Add TagInput component for tag/keyword entry
- Add SVG assets for Silo branding and UI icons
- Update API client and types for file uploads, auth, extended fields
- Update AuthContext for session-based auth flow
- Update LoginPage, ProjectsPage, SchemasPage, SettingsPage
- Fix tsconfig.node.json

Deployment:
- Update config.prod.yaml: single-binary SPA layout at /opt/silo
- Update silod.service: ReadOnlyPaths for /opt/silo
- Add scripts/deploy.sh: build, package, ship, migrate, start
- Update docker-compose.yaml and Dockerfile
- Add frontend-spec.md design document

deployments/config.prod.yaml

@@ -1,13 +1,22 @@
 # Silo Production Configuration
-# For deployment on dedicated VM using external PostgreSQL and MinIO
+# Single-binary deployment: silod serves API + React SPA
 #
-# Credentials are provided via environment variables:
+# Layout on silo.kindred.internal:
+#   /opt/silo/bin/silod          - server binary
+#   /opt/silo/web/dist/          - built React frontend (served automatically)
+#   /opt/silo/schemas/           - part number schemas
+#   /etc/silo/config.yaml        - this file
+#   /etc/silo/silod.env          - secrets (env vars)
+#
+# Credentials via environment variables (set in /etc/silo/silod.env):
 #   SILO_DB_PASSWORD
 #   SILO_MINIO_ACCESS_KEY
 #   SILO_MINIO_SECRET_KEY
+#   SILO_SESSION_SECRET
+#   SILO_ADMIN_PASSWORD
 
 server:
-  host: "127.0.0.1" # Listen only on localhost (nginx handles external traffic)
+  host: "0.0.0.0"
   port: 8080
   base_url: "https://silo.kindred.internal"
 
@@ -29,24 +38,19 @@ storage:
   region: "us-east-1"
 
 schemas:
-  directory: "/etc/silo/schemas"
+  directory: "/opt/silo/schemas"
   default: "kindred-rd"
 
 freecad:
   uri_scheme: "silo"
-  executable: "/usr/bin/freecad"
 
-# Authentication
-# Set via SILO_SESSION_SECRET, SILO_OIDC_CLIENT_SECRET, SILO_LDAP_BIND_PASSWORD env vars
 auth:
   enabled: true
   session_secret: "" # Set via SILO_SESSION_SECRET
-
   local:
     enabled: true
     default_admin_username: "admin"
     default_admin_password: "" # Set via SILO_ADMIN_PASSWORD
-
   ldap:
     enabled: true
     url: "ldaps://ipa.kindred.internal"
@@ -65,18 +69,8 @@ auth:
       viewer:
         - "cn=silo-viewers,cn=groups,cn=accounts,dc=kindred,dc=internal"
     tls_skip_verify: false
-
   oidc:
     enabled: false
-    issuer_url: "https://keycloak.kindred.internal/realms/silo"
-    client_id: "silo"
-    client_secret: "" # Set via SILO_OIDC_CLIENT_SECRET
-    redirect_url: "https://silo.kindred.internal/auth/callback"
-    scopes: ["openid", "profile", "email"]
-    admin_role: "silo-admin"
-    editor_role: "silo-editor"
-    default_role: "viewer"
-
   cors:
     allowed_origins:
       - "https://silo.kindred.internal"