#22794: fix: allow local clients to auto-pair without manual approval

When a local client (127.0.0.1/loopback) connects and needs pairing or scope/role upgrade, the silent mode should auto-approve. This fix: 1. Changes silent=true for ALL local client pairing requests (not just not-paired) 2. Adds return true after successful auto-approval to prevent rejection This resolves issues where local sub-agents cannot connect because they get stuck in pairing loop. <!-- greptile_comment --> <h3>Greptile Summary</h3> Extends auto-pairing for local clients from just initial pairing to include role and scope upgrades, preventing local sub-agents from getting stuck in pairing loops. Changes `silent` flag to apply to all local client pairing scenarios (not just "not-paired"), enabling automatic approval without manual intervention. <h3>Confidence Score: 4/5</h3> - This PR is safe to merge with low risk - it's a focused fix for local client auto-pairing - The changes correctly extend silent mode auto-approval to all local client pairing scenarios (not just initial pairing). The added early return on line 756 makes the control flow explicit. One minor consideration: when `approveDevicePairing` returns null (request doesn't exist), local clients still proceed with connection, which appears intentional for the local trust model but could mask edge cases where the pairing state is inconsistent - No files require special attention - the single-file change is straightforward and well-scoped _{Last reviewed commit: 2a913e1} <!-- greptile_other_comments_section --> <!-- /greptile_comment -->