fix(builtin): reject negative count in take

[netliomax25-code]

take([1,2,3], -1) surfaces a raw reflect.Value.Slice "slice index
out of bounds" runtime error. The negative count skips the > v.Len()
clamp and reaches v.Slice(0, -1) unmodified. Reject n < 0 the same
way repeat does and return a descriptive error.

[netliomax25-code]

gentle ping

[netliomax25-code]

any update?

[sanmaxdev]

Checked the negative-count guard and its regression coverage. The focused error case, full suite, race check, and debug build all pass.

Passed:

• go test ./...
• go test -race .
• go test -tags=expr_debug -run=TestDebugger -v ./vm
• git diff --check origin/master...HEAD

[netliomax25-code]

Thanks for running the suite and race check against this. I've left the branch as-is so your verification still matches the head commit, but I can rebase onto master whenever a maintainer wants it current.