feat(db): create systems table (#2754)

Setup UUID-based systems table with org_id, tags, system_profile,
and unique insights_id to host data locally.

https://redhat.atlassian.net/browse/RHINENG-23278

## Secure Coding Practices Checklist GitHub Link
- https://github.com/RedHatInsights/secure-coding-checklist

## Secure Coding Checklist
- [ ] Input Validation
- [ ] Output Encoding
- [ ] Authentication and Password Management
- [ ] Session Management
- [ ] Access Control
- [ ] Cryptographic Practices
- [ ] Error Handling and Logging
- [ ] Data Protection
- [ ] Communication Security
- [ ] System Configuration
- [ ] Database Security
- [ ] File Management
- [ ] Memory Management
- [x] General Coding Practices

Author: petrblaho

db/migrate/20260608090600_create_systems.rb

@@ -0,0 +1,19 @@
+class CreateSystems < ActiveRecord::Migration[7.1]
+  def change
+    create_table :systems, id: :uuid do |t|
+      t.string :account, limit: 10
+      t.string :org_id, limit: 10, null: false
+      t.string :display_name, limit: 200, null: false
+      t.jsonb :tags, null: false, default: {}
+      t.datetime :updated, null: false
+      t.datetime :created, null: false
+      t.datetime :stale_timestamp, null: false
+      t.jsonb :system_profile, null: false, default: {}
+      t.jsonb :groups, default: []
+      t.uuid :insights_id
+      t.datetime :deleted_at
+    end
+
+    add_index :systems, :insights_id, unique: true
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.1].define(version: 2026_05_28_153533) do
+ActiveRecord::Schema[8.1].define(version: 2026_06_08_090600) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "dblink"
   enable_extension "pgcrypto"
@@ -281,6 +281,21 @@
     t.index ["ref_id", "version"], name: "index_security_guides_v2_on_ref_id_and_version", unique: true
   end
 
+  create_table "systems", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
+    t.string "account", limit: 10
+    t.datetime "created", null: false
+    t.datetime "deleted_at"
+    t.string "display_name", limit: 200, null: false
+    t.jsonb "groups", default: []
+    t.uuid "insights_id"
+    t.string "org_id", limit: 10, null: false
+    t.datetime "stale_timestamp", null: false
+    t.jsonb "system_profile", default: {}, null: false
+    t.jsonb "tags", default: {}, null: false
+    t.datetime "updated", null: false
+    t.index ["insights_id"], name: "index_systems_on_insights_id", unique: true
+  end
+
   create_table "tailoring_rules_v2", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
     t.datetime "created_at", precision: nil
     t.uuid "rule_id", null: false