fix: implement critical security remediation for authentication and authorization

- Add Clerk token verification to tRPC context (server/trpc/index.ts)
- Remove client-controlled authorId/reviewedById from revisions router
- Require JWT_SECRET environment variable, remove hardcoded fallback
- Add table name validation to prevent SQL injection in backup logic
- Fix TRPCContext type to use better-sqlite3 instead of LibSQL
- Update revisions router tests to use proper tRPC v11+ API
- Add resetInMemoryState function for test isolation

Security fixes address:
- Critical: Authentication bypass via missing token verification
- Critical: User impersonation via client-controlled IDs
- High: Insecure WebSocket defaults with hardcoded secrets
- High: SQL injection vulnerability in backup logic

All tests passing (24/24).

package-lock.json

@@ -9,6 +9,7 @@
       "version": "0.1.0",
       "license": "MIT",
       "dependencies": {
+        "@clerk/backend": "^3.4.1",
         "@clerk/clerk-js": "^6.7.5",
         "@libsql/client": "^0.17.3",
         "@solidjs/router": "^0.16.1",
@@ -353,6 +354,20 @@
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       "license": "MIT"
     },
+    "node_modules/@clerk/backend": {
+      "version": "3.4.1",
+      "resolved": "https://registry.npmjs.org/@clerk/backend/-/backend-3.4.1.tgz",
+      "integrity": "sha512-+Tgo1uPEFpBRvyFW3JtPbrTMRgiP+pWBo9gi2tTB0AxEqR2I/kSYy5l3+KqWciUpbVZtVvLXm1j+NEE2WEG+jg==",
+      "license": "MIT",
+      "dependencies": {
+        "@clerk/shared": "^4.8.5",
+        "standardwebhooks": "^1.0.0",
+        "tslib": "2.8.1"
+      },
+      "engines": {
+        "node": ">=20.9.0"
+      }
+    },
     "node_modules/@clerk/clerk-js": {
       "version": "6.7.5",
       "resolved": "https://registry.npmjs.org/@clerk/clerk-js/-/clerk-js-6.7.5.tgz",
@@ -392,9 +407,9 @@
       }
     },
     "node_modules/@clerk/shared": {
-      "version": "4.8.3",
-      "resolved": "https://registry.npmjs.org/@clerk/shared/-/shared-4.8.3.tgz",
-      "integrity": "sha512-HZViZBCTfOR2OreSBDMXcIRPgYiiYCE+GCCPrpjq/ZPcA6OsGiRCIQgUoGgGdAoFgr6Hk0TT00hnVK7g0qRKqQ==",
+      "version": "4.8.5",
+      "resolved": "https://registry.npmjs.org/@clerk/shared/-/shared-4.8.5.tgz",
+      "integrity": "sha512-YxgUWHoKEXEbRPWPEcB2Q0o+NJkDc0/zQRp4QCsnGIM5e32hlBUwxcYpyDjDlZ2lYB+GUXHuEc3KETnxWGp26g==",
       "hasInstallScript": true,
       "license": "MIT",
       "dependencies": {
@@ -3026,6 +3041,12 @@
         "solid-js": "^1.8.6"
       }
     },
+    "node_modules/@stablelib/base64": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@stablelib/base64/-/base64-1.0.1.tgz",
+      "integrity": "sha512-1bnPQqSxSuc3Ii6MhBysoWCg58j97aUjuCSZrGSmDxNqtytIi0k8utUenAwTZN4V5mXXYGsVUI9zeBqy+jBOSQ==",
+      "license": "MIT"
+    },
     "node_modules/@stripe/stripe-js": {
       "version": "5.6.0",
       "resolved": "https://registry.npmjs.org/@stripe/stripe-js/-/stripe-js-5.6.0.tgz",
@@ -6173,6 +6194,12 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/fast-sha256": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/fast-sha256/-/fast-sha256-1.3.0.tgz",
+      "integrity": "sha512-n11RGP/lrWEFI/bWdygLxhI+pVeo1ZYIVwvvPkW7azl/rOy+F3HYRZ2K5zeE9mmkhQppyv9sQFx0JM9UabnpPQ==",
+      "license": "Unlicense"
+    },
     "node_modules/fast-stable-stringify": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/fast-stable-stringify/-/fast-stable-stringify-1.0.0.tgz",
@@ -9945,6 +9972,16 @@
         "node": ">=8"
       }
     },
+    "node_modules/standardwebhooks": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/standardwebhooks/-/standardwebhooks-1.0.0.tgz",
+      "integrity": "sha512-BbHGOQK9olHPMvQNHWul6MYlrRTAOKn03rOe4A8O3CLWhNf4YHBqq2HJKKC+sfqpxiBY52pNeesD6jIiLDz8jg==",
+      "license": "MIT",
+      "dependencies": {
+        "@stablelib/base64": "^1.0.0",
+        "fast-sha256": "^1.3.0"
+      }
+    },
     "node_modules/statuses": {
       "version": "1.5.0",
       "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.5.0.tgz",