fix(core): return raw host objects (File/Blob) from form.data

[LouisHaftmann]

Problem

form.data is wrapped by on-change for dirty tracking. on-change lazily proxies every nested object on read and treats File/Blob as plain objects — so form.data.files[0] returned a Proxy wrapping the File. Native accessors (.name / .size / .type / .arrayBuffer()) are bound to internal slots and throw TypeError: Illegal invocation when the receiver is the proxy instead of the real object. toRaw doesn't unwrap it (it's an on-change proxy, not a Vue reactive), and field.value only worked by accident.

Vue's reactive already leaves host objects raw (getTargetType → INVALID), so on-change was the sole culprit.

Fix

on-change 6.0.2 (latest) has no leaf/allow-list hook, so this adds a pnpm patch to its prepareValue: any non-plain object that isn't a tracked builtin (Array / Date / Map / Set / typed array) is returned by reference and never wrapped. This fixes form.data, field.value, and field.model at once (all read through the proxy), preserves object identity — so dirty tracking still fires on identity change with no blob deep-diff — and confirms klona/full clones File by reference.

Tests

• core: form.data.<path> returns raw File/Blob with working native getters; field.value identity stays raw after an unrelated change + re-validation; File in sourceValues survives clone + reset(); dirty tracking fires on file change.
• vue: field.model returns the raw File.

Notes

• Typed arrays remain proxied (they're isBuiltinWithMutableMethods, which on-change intentionally tracks). Acceptance only required File/Blob.
• Two failures on this branch (core > field > readonly, entire react suite) are pre-existing on master and unrelated: Vue warn dedup, and react-test-renderer.act removed in React 19.

🤖 Generated with Claude Code