feat(jq): support external-argument flags (--arg, --argjson, --rawfile, --slurpfile, --args, --jsonargs) (#291)

* feat(jq): add support for named-argument flags (--arg, --argjson, --rawf

Agent-Id: agent-adffc8b9-56e7-42e1-9640-29e54e91cb68
Linked-Note-Id: 5eacc9eb-3c60-4792-a92f-e032866df682

* test(jq): add jq --arg comparison fixtures

Signed-off-by: Lars Trieloff <lars@trieloff.net>

* feat(jq): add support for positional-argument flags (--args, --jsonargs)

Agent-Id: agent-5e21eaf1-efeb-4038-8f3b-ee7539cebc9a
Linked-Note-Id: 704d1169-b7c6-4f47-b565-d020c66a30ea

* test(jq): add jq --args/--jsonargs comparison fixtures

Signed-off-by: Lars Trieloff <lars@trieloff.net>

* test(jq): cover multiple --arg flags together

Signed-off-by: Lars Trieloff <lars@trieloff.net>

* fix(jq): keep __proto__ key in $ARGS.named to match real jq

Signed-off-by: Lars Trieloff <lars@trieloff.net>

* chore: add changeset for jq external-argument flags

Signed-off-by: Lars Trieloff <lars@trieloff.net>

* fix(jq): thread JSON stream limits through external-argument parsing

parseJsonStream now requires a limits arg after the main refactor; hoist jsonLimits so --argjson/--jsonargs/--slurpfile pass it.

Signed-off-by: Lars Trieloff <lars@trieloff.net>

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Signed-off-by: Lars Trieloff <lars@trieloff.net>
Co-authored-by: Augment Code <noreply@augmentcode.com>