docs(strong): record age-key issuance and the 3 bootstrap.sh bugs found fixing it

strong now has its own age key (issued over LAN via --no-mesh),
pubkey recorded in inventory.yaml. Not yet granted to any secrets
file - that's a separate decision.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

hosts/strong.yaml

@@ -26,6 +26,7 @@ notes:
 - "First step of the planned library-SSD migration \u2014 see .hermes/plans/2026-06-03_110000-library-ssd-migration-to-ludo-mini.md\
   \ (filename kept as-is, it's a historical planning doc). Only Phase 1 (Proxmox install + cluster join)\
   \ is done; no physical drive move, service migration, or GPU passthrough has happened yet."
+age_pubkey: age1rtwvdct6avjkr3cyxv3vue3vqx4d524fjfr3vk7xrnvyrylnry5sm54sn4
 see_also:
 - hosts/strong.md
 mcp_endpoint: https://mcp.hubris.network/mcp