Phase 3: Optimize & clean up — unified projects, account enhancements, new tenant fix

- Unify reserve_components + capital_projects into single projects model with
  full CRUD backend and new Projects page frontend
- Rewrite Capital Planning to read from unified projects/planning endpoint;
  add empty state directing users to Projects page when no planning items exist
- Add default designation to assessment groups with auto-set on first creation;
  units now require an assessment group (pre-populated with default)
- Add primary account designation (one per fund type) and balance adjustment
  via journal entries against equity offset accounts (3000/3100)
- Add computed investment fields (interest earned, maturity value, days remaining)
  with PostgreSQL date arithmetic fix for DATE - DATE integer result
- Restructure sidebar: investments in Accounts tab, Year-End under Reports,
  Planning section with Projects and Capital Planning
- Fix new tenant creation seeding unwanted default chart of accounts —
  new tenants now start with a blank slate

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/modules/units/units.service.ts

@@ -32,10 +32,29 @@ export class UnitsService {
     const existing = await this.tenant.query('SELECT id FROM units WHERE unit_number = $1', [dto.unit_number]);
     if (existing.length) throw new BadRequestException(`Unit ${dto.unit_number} already exists`);
 
+    // Resolve assessment group: use provided, fall back to default, or error
+    let groupId = dto.assessment_group_id || null;
+    if (!groupId) {
+      const defaultGroup = await this.tenant.query(
+        'SELECT id FROM assessment_groups WHERE is_default = true AND is_active = true LIMIT 1',
+      );
+      if (defaultGroup.length) {
+        groupId = defaultGroup[0].id;
+      } else {
+        // Check if any groups exist at all
+        const anyGroup = await this.tenant.query('SELECT id FROM assessment_groups WHERE is_active = true LIMIT 1');
+        if (!anyGroup.length) {
+          throw new BadRequestException('An assessment group must exist before creating units. Please create an assessment group first.');
+        }
+        // Use the first available group
+        groupId = anyGroup[0].id;
+      }
+    }
+
     const rows = await this.tenant.query(
       `INSERT INTO units (unit_number, address_line1, city, state, zip_code, owner_name, owner_email, owner_phone, monthly_assessment, assessment_group_id)
        VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10) RETURNING *`,
-      [dto.unit_number, dto.address_line1, dto.city, dto.state, dto.zip_code, dto.owner_name, dto.owner_email, dto.owner_phone, dto.monthly_assessment || 0, dto.assessment_group_id || null],
+      [dto.unit_number, dto.address_line1, dto.city, dto.state, dto.zip_code, dto.owner_name, dto.owner_email, dto.owner_phone, dto.monthly_assessment || 0, groupId],
     );
     return rows[0];
   }