fix(core): consolidate ID generation to prevent HTTP self-hosted crashes (#3977)

* fix(core): consolidate ID generation to prevent HTTP self-hosted crashes

crypto.randomUUID() requires a secure context (HTTPS) in browsers,
causing white-screen crashes on self-hosted HTTP deployments. This
replaces all direct usage of crypto.randomUUID(), nanoid, and the uuid
package with a central utility that falls back to crypto.getRandomValues()
which works in all contexts.

- Add generateId(), generateShortId(), isValidUuid() in @/lib/core/utils/uuid
- Replace crypto.randomUUID() imports across ~220 server + client files
- Replace nanoid imports with generateShortId()
- Replace uuid package validate with isValidUuid()
- Remove nanoid dependency from apps/sim and packages/testing
- Remove browser polyfill script from layout.tsx
- Update test mocks to target @/lib/core/utils/uuid
- Update CLAUDE.md, AGENTS.md, cursor rules, claude rules

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

* update bunlock

* fix(core): remove UUID_REGEX shim, use isValidUuid directly

* fix(core): remove deprecated uuid mock helpers that use vi.doMock

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

packages/testing/package.json

@@ -56,7 +56,5 @@
     "typescript": "^5.7.3",
     "vitest": "^3.0.8"
   },
-  "dependencies": {
-    "nanoid": "5.1.6"
-  }
+  "dependencies": {}
 }