chore: Replace lodash with es-toolkit (#12281)

* chore: Replace lodash with es-toolkit

Migrate all direct lodash imports to es-toolkit/compat for a smaller,
faster, lodash-compatible utility library. Transitive lodash usage from
other packages remains unchanged.

* fix: Restore isPlainObject semantics in CanCan policy

The lodash migration aliased `isObject` to `lodash/isPlainObject` and
the codemod incorrectly mapped the local name to es-toolkit's `isObject`,
which also returns true for arrays and functions. This caused condition
objects in policy definitions to be skipped, breaking authorization
checks across the codebase.

* fix: Restore unicode-aware length counting in validators

es-toolkit/compat's size() returns string.length, while lodash's _.size()
counts unicode code points. Switch to [...value].length to preserve the
previous behavior so multi-byte characters like emoji count as one.

vite.config.ts

@@ -239,8 +239,8 @@ export default () =>
                 priority: 20,
               },
               {
-                name: "vendor-lodash",
-                test: /node_modules[\\/](lodash|lodash-es)/,
+                name: "vendor-es-toolkit",
+                test: /node_modules[\\/]es-toolkit/,
                 priority: 20,
               },
               {