feat: Add currency management feature with CRUD operations

- Introduced a new template for currency overview and management (`currencies.html`).
- Updated footer to include attribution to AllYouCanGET.
- Added "Currencies" link to the main navigation header.
- Implemented end-to-end tests for currency creation, update, and activation toggling.
- Created unit tests for currency API endpoints, including creation, updating, and activation toggling.
- Added a fixture to seed default currencies for testing.
- Enhanced database setup tests to ensure proper seeding and migration handling.

scripts/migrations/20251021_add_currency_and_unit_fields.sql

@@ -7,23 +7,23 @@ BEGIN;
 
 -- CAPEX / OPEX
 ALTER TABLE capex
-    ADD COLUMN currency_code VARCHAR(3) NOT NULL DEFAULT 'USD';
+    ADD COLUMN IF NOT EXISTS currency_code VARCHAR(3) NOT NULL DEFAULT 'USD';
 
 ALTER TABLE opex
-    ADD COLUMN currency_code VARCHAR(3) NOT NULL DEFAULT 'USD';
+    ADD COLUMN IF NOT EXISTS currency_code VARCHAR(3) NOT NULL DEFAULT 'USD';
 
 -- Consumption tracking
 ALTER TABLE consumption
-    ADD COLUMN unit_name VARCHAR(64);
+    ADD COLUMN IF NOT EXISTS unit_name VARCHAR(64);
 
 ALTER TABLE consumption
-    ADD COLUMN unit_symbol VARCHAR(16);
+    ADD COLUMN IF NOT EXISTS unit_symbol VARCHAR(16);
 
 -- Production output
 ALTER TABLE production_output
-    ADD COLUMN unit_name VARCHAR(64);
+    ADD COLUMN IF NOT EXISTS unit_name VARCHAR(64);
 
 ALTER TABLE production_output
-    ADD COLUMN unit_symbol VARCHAR(16);
+    ADD COLUMN IF NOT EXISTS unit_symbol VARCHAR(16);
 
 COMMIT;