@std/toml: Inline array stringification mishandles edge cases

Inline array stringification has multiple bugs in the current implementation. Running:
```ts
import * as toml from "@std/toml";

// Primitive array bugs
console.log(toml.stringify({x: [Infinity, -Infinity, NaN]}));
console.log(toml.stringify({x: [new Date(0)]}));

// Object-only array bug
try {
console.log(toml.stringify({x: [null]}));
} catch (e) {
console.log("got error", e);
}

// Mixed-type array bugs
console.log(toml.stringify({x: [Infinity, -Infinity, NaN, {}]}));
console.log(toml.stringify({x: [new Date(0), {}]}));
try {
console.log(toml.stringify({x: [1, null]}));
} catch (e) {
console.log("got error", e);
}
```
Will log:
```
x = [null,null,null] // expected: x = [inf, -inf, nan]

x = ["1970-01-01T00:00:00.000Z"] // expected: x = [1970-01-01T00:00:00.000Z]

got error TypeError: Cannot convert undefined or null to object // expected: ???
at Object.keys ()
at Dumper.#printObject (https://jsr.io/@std/toml/1.0.11/stringify.ts:51:26)
at Dumper.#printObject (https://jsr.io/@std/toml/1.0.11/stringify.ts:83:42)
at Dumper.dump (https://jsr.io/@std/toml/1.0.11/stringify.ts:45:36)
at Module.stringify (https://jsr.io/@std/toml/1.0.11/stringify.ts:294:26)

x = [Infinity,-Infinity,NaN,{}] // expected: x = [inf, -inf, nan, {}]

x = ["1970-01-01T00:00:00.000",{}] // expected: x = [1970-01-01T00:00:00.000Z, {}]

got error Error: Should never reach // expected: ???
at Dumper.#printAsInlineValue (https://jsr.io/@std/toml/1.0.11/stringify.ts:151:15)
at https://jsr.io/@std/toml/1.0.11/stringify.ts:87:64
at Array.map ()
at Dumper.#printObject (https://jsr.io/@std/toml/1.0.11/stringify.ts:87:29)
at Dumper.dump (https://jsr.io/@std/toml/1.0.11/stringify.ts:45:36)
at Module.stringify (https://jsr.io/@std/toml/1.0.11/stringify.ts:294:26)
```

Since TOML doesn't support `null` values, I'm not sure how the `{x: [null]}` and `{x: [1, null]}` cases should be handled, but I feel at the very least a better error message should be given. The quotation marks around the date is a somewhat minor bug as it causes the date to reparse as a string instead of a `Date`. The mishandling of `Infinity`/`NaN` is a more severe bug as both cases (stringifying to `null` and stringifying to `Infinity`/`NaN`) causes it to no longer parse.

I can attempt a PR to fix this, but I'm wondering if it's even necessary to stringify "primitive" arrays using `JSON.stringify`. This is causing the first 2 bugs here, and I'm not sure that it meaningfully improves runtime compared to just using the mixed-type array stringification.

**Environment**
- OS: Arch Linux
- deno version: 2.8.1
- std version: 1.0.11