fix(hermes): revert hard rpi5 requirement (it stranded worker)

Requiring rpi5 while the historical hostname exclusion list removes the very rpi5
nodes that currently have headroom (titan-04/06) left only loaded rpi5s
(titan-05/07/11), so the agent could not schedule and worker went down. Revert to
rpi5-PREFERRED (soft) so it schedules again; proper rpi5 placement needs the
exclusion list refreshed against current node health/capacity, tracked separately.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BvMSXH8VH2tMWXanb8SJdf

services/hermes/agent-deployment.yaml

@@ -108,12 +108,6 @@ spec:
                   - key: node-role.kubernetes.io/worker
                     operator: In
                     values: ["true"]
-                  # Require rpi5: the agent is heavy and an rpi4 is slow enough to
-                  # risk tripping the /api/status liveness probe. rpi5 storage
-                  # workers only, excluding the saturated/known-flaky ones.
-                  - key: hardware
-                    operator: In
-                    values: [rpi5]
                   - key: kubernetes.io/hostname
                     operator: NotIn
                     values: [titan-04, titan-06, titan-08, titan-13, titan-14, titan-17, titan-18, titan-19]