ADR-0013: installer — installer/agents/hermes.sh writes default /etc/hal0/agents/hermes.toml + workspace dir

[thinmintdev]

Implements the bootstrap path for ADR-0013 — MCP-client allow-list for bundled agents.

Scope

In installer/agents/hermes.sh:

• Create /var/lib/hal0/agents/hermes/workspace/ with correct perms (hal0:hal0, 0750).
• Write /etc/hal0/agents/hermes.toml with:
  • hal0-admin + hal0-memory (builtin = true).
  • One external MCP wired by default — filesystem MCP scoped to the workspace — satisfies the v0.3 ships-when criterion "at least one MCP-client external source connectable from a bundled agent" (PLAN §1).
  • Schema-version = 1, default tools.allow / tools.gated populated per ADR §6.

In the Hermes bootstrap state machine (per hermes-bootstrap-plan-2026-05-23.md):

• mcp_wire phase reads this file, registers connections with Hermes's MCP client, proceeds.
• Failure to connect to a non-builtin MCP logs + continues (does NOT fail bootstrap).

Acceptance

• installer/agents/hermes.sh is idempotent (re-run preserves user edits to TOML).
• Hermes bootstrap on a fresh LXC results in a working filesystem MCP reachable from Hermes.
• δ harness row covers the install → MCP-reachable round-trip.

Depends on

• ADR-0013 backend issue (mcp_client.py runtime must exist).
• Hermes bootstrap scaffold (Hermes bootstrap scaffold: phase pipeline + provision.json + CLI #238).