fix: bump handlebars to 4.7.9 (CVE-2026-33937) (#19288)

## Summary
- Bumps `handlebars` from `^4.7.8` to `^4.7.9` in
`packages/twenty-shared`

## Why
- **CVE-2026-33937** — Prototype pollution via crafted template input
- **GHSA-2w6w-674q-4c4q** — Related handlebars security advisory
- Severity: **Critical** (CVSS 9.8)
- Detected by Trivy and Grype scanning `twentycrm/twenty:v1.20.0`

## What changed
- `packages/twenty-shared/package.json`: `"handlebars": "^4.7.8"` →
`"^4.7.9"`
- `yarn.lock`: updated accordingly

## Impact
`handlebars` is used in `packages/twenty-shared` for template
evaluation. The fix patches the prototype pollution vector without any
API changes.

## Test plan
- [ ] `yarn build` passes
- [ ] `yarn test` passes in twenty-shared
- [ ] Template evaluation works as before

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Abdullah <125115953+mabdullahabaid@users.noreply.github.com>

packages/twenty-shared/package.json

@@ -32,7 +32,7 @@
     "@sniptt/guards": "^0.2.0",
     "class-validator": "^0.14.0",
     "expr-eval-fork": "3.0.3",
-    "handlebars": "^4.7.8",
+    "handlebars": "^4.7.9",
     "libphonenumber-js": "^1.10.26",
     "lodash.camelcase": "^4.3.0",
     "qs": "^6.11.2",

yarn.lock

@@ -40360,7 +40360,25 @@ __metadata:
   languageName: node
   linkType: hard
 
-"handlebars@npm:*, handlebars@npm:4.7.8, handlebars@npm:^4.7.7, handlebars@npm:^4.7.8":
+"handlebars@npm:*, handlebars@npm:^4.7.7, handlebars@npm:^4.7.9":
+  version: 4.7.9
+  resolution: "handlebars@npm:4.7.9"
+  dependencies:
+    minimist: "npm:^1.2.5"
+    neo-async: "npm:^2.6.2"
+    source-map: "npm:^0.6.1"
+    uglify-js: "npm:^3.1.4"
+    wordwrap: "npm:^1.0.0"
+  dependenciesMeta:
+    uglify-js:
+      optional: true
+  bin:
+    handlebars: bin/handlebars
+  checksum: 10c0/22f8105a7e68e81aff2662bb434edf05f757d21d850731d71cec886d69c10cd33d3c43e34b2892968ec62de8241611851d3d0674c8ef324ea3e01dc66262faa9
+  languageName: node
+  linkType: hard
+
+"handlebars@npm:4.7.8":
   version: 4.7.8
   resolution: "handlebars@npm:4.7.8"
   dependencies:
@@ -60186,7 +60204,7 @@ __metadata:
     class-validator: "npm:^0.14.0"
     expr-eval-fork: "npm:3.0.3"
     glob: "npm:^11.1.0"
-    handlebars: "npm:^4.7.8"
+    handlebars: "npm:^4.7.9"
     libphonenumber-js: "npm:^1.10.26"
     lodash.camelcase: "npm:^4.3.0"
     qs: "npm:^6.11.2"