Add job application tracker (admin-only)

Full CRUD GraphQL API for tracking job applications with status workflow.
Frontend component in CV view, hidden from print. Login now redirects to
intended route after auth via query param.

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

backend/models/models.go

@@ -66,3 +66,17 @@ type Rowing struct {
 	TimePer500m float64        `json:"timePer500m"`
 	Calories    float64        `json:"calories"`
 }
+
+type JobApplication struct {
+	ID        uint           `gorm:"primarykey" json:"id"`
+	CreatedAt time.Time      `json:"createdAt"`
+	UpdatedAt time.Time      `json:"updatedAt"`
+	DeletedAt gorm.DeletedAt `gorm:"index" json:"deletedAt"`
+	JobTitle  string         `gorm:"not null" json:"jobTitle"`
+	Company   string         `gorm:"not null" json:"company"`
+	Location  *string        `json:"location"`
+	URL       *string        `json:"url"`
+	Status    string         `gorm:"not null" json:"status"`
+	Notes     *string        `json:"notes"`
+	AppliedAt *time.Time     `json:"appliedAt"`
+}