Restore exact-pin fresh-clone initialization

[bigboateng]

Problem

A fresh clone can contain an exact committed runtime pin but no machine-local controller state. Boatstack classified that state as conflicting, so installation.initialize could not run.

Root cause

Runtime observation did not distinguish an absent state file from an existing state with an empty runtime identity. Any present pin therefore forced the conflicting state before bootstrap.

Invariant restored

A committed pin is bootstrap evidence only when the controller state is absent and the pin matches the executing candidate plus its immutable installed artifact. Missing, corrupt, malformed, or mismatched evidence remains fail-closed.

Changes

• distinguish absent controller state from an existing durable state
• admit exact committed pins for fresh-clone initialization
• preserve stale and conflicting classifications for invalid evidence
• tell installers to commit .boatstack/runtime.json
• isolate installer contract tests from the global runtime store

Verification

• fresh clone initializes and reports healthy in one invocation
• mismatched pin is refused without controller-state mutation
• missing immutable runtime remains stale
• complete sharded Go suite: 154 tests
• Python repository contracts: 27 tests
• Go race tests, vet, build, release-note validation, and diff checks

Release note: release-notes/2026-08-11-fresh-clone-runtime-bootstrap.md

No legacy-state migration is included.