feat: plan native endpoints and local host bindings

[roodboi]

Native configuration could declare managed env references and routes, but could not connect an environment destination to a typed endpoint or inherit a local host target in a linked worktree. This adds pure endpoint planning and allowlisted host binding resolution to the bundled compiler and CLI.

Service, route and logical host-binding references preserve explicit target kinds. Route endpoints use central origin resolution; service and host addresses stay symbolic until an execution backend can provide them. Project and local bindings merge by logical name with provenance and null removals. An endpoint cannot replace an existing managed destination, and host invocations refuse direct guest-service addressing instead of guessing connectivity.

The transport negotiates the additive endpoint capability and cross-checks emitted targets, original local source claims, calling context and preserved managed baselines. Endpoint-free callers retain their wire/hash behavior. Planning performs no hooks, DNS, trust or runtime effects; native-authored execution remains fenced.

Validation:

• Pinned Rust formatting, Clippy with warnings denied, and 83 tests.
• 243 independent JSON Schema/compiler cases.
• 153 relocated compiled CLI checks, including real linked worktrees, inheritance opt-out, local removals, collisions and no effects.
• Full repository typecheck and lint passed. The full suite passed: 2,638 tests, 68 gated skips, zero failures; the DB task reused a valid cache.
• Hack-managed Linux toolchain: 99 endpoint tests passed.
• Signed private bundle at this head: 35 installed checks passed with host Bun/Rust absent, including linked-worktree inheritance, endpoint collision/removal, repeat install and deselect/reselect. No release was published.
• Independent source review passed. All ten exact-head hosted CI jobs and Graphite passed: https://github.com/hack-dance/hack/actions/runs/37671901801.

Release signal: feat adds offline planning capabilities. Native execution/admission, advanced workload fields and locked adoption remain separate work. Refs HACK-1220.

[linear-code]

HACK-1220