[tiny-modules] tinyskills: move the per-run skill log format into tinyskills #7570

Parent: #7531

Context

hosting.enabled (config/schema/hosting.rs:22, checked at hosting/mod.rs:50) exists, but hosting has no DomainSet group and no ToolGroup, and its registry record is compiled and trusted regardless.

What moves

• [hosting] enabled folds into [components] hosting (migration)
• Add the hosting tools to a ToolGroup and a DomainSet/ComponentSet entry so hosts and config can narrow them
• modules::ensure_loaded("tinyhosts") refuses when off

What stays in OpenHuman

Wiring only; credential gating in tools/ops.rs stays.

Upstream target

None (host-only). Uses the E1 framework.

Host adapter after the move

Off ⇒ no module load, no hosting tools, modules.list reports disabled.

Acceptance criteria

• Host-only change: no upstream PR or module release needed for the toggle itself (the module keeps its released pin)
• One-shot config migration from the old key(s), with a test
• Component off: module never downloaded or loaded, no tools, no background services, RPC namespace answers COMPONENT_DISABLED, modules.list/about_app show it disabled
• Component on: behaviour unchanged
• pnpm rust:layout, cargo check --manifest-path Cargo.toml, cargo check --manifest-path crates/openhuman-app/Cargo.toml, affected pnpm debug rust <filter> green
• Tests: component off ⇒ no hosting tools and no module load; old hosting.enabled=false migrates

Depends on

#7525 (E1 [components] framework, leaf E1.1)