Add Zod validation, fix mass assignment, remove test endpoints and dead code

- Add centralized Zod schemas (server/utils/schemas.js) and validateBody
  utility for all API endpoints
- Fix critical mass assignment in member creation: raw body no longer
  passed to new Member(), only validated fields (email, name, circle,
  contributionTier) are accepted
- Apply Zod validation to login, profile patch, event registration,
  updates, verify-payment, and admin event creation endpoints
- Fix logout cookie flags to match login (httpOnly: true, secure
  conditional on NODE_ENV)
- Delete unauthenticated test/debug endpoints (test-connection,
  test-subscription, test-bot)
- Remove sensitive console.log statements from Helcim and member
  endpoints
- Remove unused bcryptjs dependency
- Add 10MB file size limit on image uploads
- Use runtime config for JWT secret across all endpoints
- Add 38 validation tests (117 total, all passing)

package-lock.json

@@ -14,7 +14,6 @@
         "@nuxt/ui": "^4.0.0",
         "@nuxtjs/plausible": "^3.0.1",
         "@slack/web-api": "^7.10.0",
-        "bcryptjs": "^3.0.2",
         "chrono-node": "^2.8.4",
         "cloudinary": "^2.7.0",
         "eslint": "^9.34.0",
@@ -7606,15 +7605,6 @@
         "node": ">=6.0.0"
       }
     },
-    "node_modules/bcryptjs": {
-      "version": "3.0.3",
-      "resolved": "https://registry.npmjs.org/bcryptjs/-/bcryptjs-3.0.3.tgz",
-      "integrity": "sha512-GlF5wPWnSa/X5LKM1o0wz0suXIINz1iHRLvTS+sLyi7XPbe5ycmYI3DlZqVGZZtDgl4DmasFg7gOB3JYbphV5g==",
-      "license": "BSD-3-Clause",
-      "bin": {
-        "bcrypt": "bin/bcrypt"
-      }
-    },
     "node_modules/bidi-js": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/bidi-js/-/bidi-js-1.0.3.tgz",