feat(auth): phase 3 — replace Supabase GoTrue with bcryptjs+jose

Custom auth stack: bcryptjs password hashing (cost 10, GoTrue-compatible),
jose JWT session cookies (edge-safe, 8hr TTL), new API routes for
login/logout/reset/change-password, middleware rewritten to JWT-only
verification with no DB access. All 38 protected pages and API routes
migrated from supabase.auth.getUser() to getSession(). Supabase .from()
queries retained for Phase 4. lib/db/index.ts refactored to lazy Proxy
singleton to avoid module-level throw during Next.js build.

tsc: clean, build: clean, tests: 4/4 passed

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

package-lock.json

@@ -11,9 +11,11 @@
         "@anthropic-ai/sdk": "^0.111.0",
         "@supabase/ssr": "^0.12.0",
         "@supabase/supabase-js": "^2.110.2",
+        "bcryptjs": "^3.0.3",
         "drizzle-orm": "^0.45.2",
         "file-type": "^22.0.1",
         "idb": "^8.0.3",
+        "jose": "^6.2.4",
         "next": "^15.5.20",
         "openai": "^6.46.0",
         "pdf-lib": "^1.17.1",
@@ -26,6 +28,7 @@
         "@tailwindcss/postcss": "^4",
         "@testing-library/jest-dom": "^6.9.1",
         "@testing-library/react": "^16.3.2",
+        "@types/bcryptjs": "^2.4.6",
         "@types/node": "^20",
         "@types/pg": "^8.20.0",
         "@types/qrcode": "^1.5.6",
@@ -3350,6 +3353,13 @@
       "license": "MIT",
       "peer": true
     },
+    "node_modules/@types/bcryptjs": {
+      "version": "2.4.6",
+      "resolved": "https://registry.npmjs.org/@types/bcryptjs/-/bcryptjs-2.4.6.tgz",
+      "integrity": "sha512-9xlo6R2qDs5uixm0bcIqCeMCE6HiQsIyel9KQySStiyqNl2tnj2mP3DX1Nf56MD6KMenNNlBBsy3LJ7gUEQPXQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/chai": {
       "version": "5.2.3",
       "resolved": "https://registry.npmjs.org/@types/chai/-/chai-5.2.3.tgz",
@@ -4555,6 +4565,15 @@
         "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",
@@ -7541,6 +7560,15 @@
         "jiti": "lib/jiti-cli.mjs"
       }
     },
+    "node_modules/jose": {
+      "version": "6.2.4",
+      "resolved": "https://registry.npmjs.org/jose/-/jose-6.2.4.tgz",
+      "integrity": "sha512-N8acGzVsQy6M/fjFcxtysNc4Q379TcM5dM/qKkNtsHFji88yANnXTr7BLeP75iPnFwBfQzM/jg2BZ9+HZrHCZA==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/js-tokens": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-4.0.0.tgz",