fix(omp): expose injected Paseo tools directly

[perezd]

Summary

• model OMP's optional host-tool loadMode field in the typed RPC definition
• serialize every caller-scoped Paseo host tool with loadMode: "essential"
• preserve full-catalog parity with Claude's MCP integration without introducing a Paseo allowlist
• document why omitting the field changes OMP tools into xd:// devices

Problem

Paseo successfully sends its caller-scoped catalog through OMP's set_host_tools, but omits loadMode. OMP 17.1.2 defaults non-built-in host-tool names to discoverable, mounting tools such as create_agent and browser_list_tabs under xd:// instead of exposing them as direct function tools. The successful RPC response therefore did not produce the direct unprefixed inventory promised by the OMP provider.

This was confirmed with the upstream OMP maintainers in can1357/oh-my-pi#6552. Claude's working MCP path registers the complete caller-scoped catalog as direct tools, so the OMP native path now does the same for every catalog entry.

Verification

• npx vitest run packages/server/src/server/agent/providers/omp/host-tools.test.ts --bail=1 — 3 passed
• npm run build:server — passed
• npm run typecheck — passed after rebuilding workspace declarations
• npm run lint — passed
• npm run format:check — passed
• isolated OMP 17.1.2 RPC probe: omitted mode mounted the probe under xd:// and excluded it from dumpTools; loadMode: "essential" placed it in dumpTools

No docs/superpowers plans, specs, or workflow collateral are included.