Greptile Summary

This PR combines three changes: (1) the headline fix—ensureAgentConfigIndex in ui/src/ui/app-render.ts lazily inserts a minimal config entry for auto-discovered agents so their settings changes are tracked and the save button becomes active; (2) a Telegram webhook self-signed certificate feature (webhookCertPath), which is clean and well-tested; and (3) a gateway refactor that removes nodeSendToSession / nodeSendToAllSubscribed calls for chat, health, and tick events, relying entirely on broadcast for delivery.

Key findings:

• The ensureAgentConfigIndex logic is correct and all affected handlers are updated consistently.
• Two dead required parameters were left behind by the nodeSendToSession cleanup: nodeSendToSession in the ChatAbortOps type (src/gateway/chat-abort.ts) and nodeSendToAllSubscribed in startGatewayMaintenanceTimers (src/gateway/server-maintenance.ts). Both parameters are declared but never called, creating unnecessary coupling where all callers must still provide them.
• The webhook webhookCertPath addition is clean and comprehensively tested.

Confidence Score: 4/5

• This PR is safe to merge. The core UI fix is correct, the gateway refactor is well-tested, and the dead parameters don't affect runtime behavior.
• The headline fix for agent settings save is logically correct and all affected handlers are updated consistently. The gateway nodeSendToSession removal is accompanied by comprehensive test updates. The two dead required parameters (nodeSendToSession in ChatAbortOps and nodeSendToAllSubscribed in startGatewayMaintenanceTimers) are technical debt left behind but don't introduce bugs—callers will still work, just with unnecessary coupling. The Telegram webhook changes are clean.
• src/gateway/chat-abort.ts and src/gateway/server-maintenance.ts — remove the dead nodeSendToSession and nodeSendToAllSubscribed fields to eliminate unnecessary coupling.

_{Last reviewed commit: 81ff1af}