Console API: console.log, console.error, console.warn #106

Implement the Console API as built-in JS globals.

Scope#

Console Object#

• Register console as a global object in the JS VM during init_builtins()
• Implement as a plain object with native function methods

Methods#

• console.log(...args) — format arguments and write to stdout
• console.error(...args) — format arguments and write to stderr
• console.warn(...args) — format arguments and write to stderr
• console.info(...args) — alias for console.log
• console.debug(...args) — alias for console.log (or no-op)

Formatting#

• Convert each argument to its string representation using the existing to_js_string() on Value
• Separate multiple arguments with spaces
• Objects should show [object Object] or a more useful representation
• Arrays should show their contents

Output Channel#

• Provide a configurable output sink (trait or callback) so the browser can redirect console output to a dev tools panel later
• Default implementation writes to stdout/stderr

Integration#

• Works in the existing evaluate() / evaluate_with_preamble() API
• No DOM dependency required — pure JS engine feature

Acceptance Criteria#

• console.log("hello") prints to stdout
• console.error("oops") prints to stderr
• Multiple arguments: console.log("a", 1, true) → a 1 true
• Object formatting: console.log({x: 1}) → reasonable output
• console.log does not throw — always returns undefined
• Works with the existing Test262 infrastructure (can be used as print() replacement)

Phase 11 — DOM-JS Bindings (issue 1 of 8). No dependencies on other Phase 11 issues.