refactor: compose local and distributed runtimes

[flexdinesh]

• Compose local and remote runtimes around shared ingestion, review services, HTTP lifecycle, and Go storage/queue contracts; preserve stable identities, immutable observations, deduplication, and retention.
• Add servediff PATH for direct ingestion, checkout watching, UI/REST/MCP, host binding, and confirmed singleton replacement. Pin the browser review when commenting to preserve drafts.
• Add remote-only sync and plugin delivery with bearer authentication, durable SQLite jobs, fenced leases, retries, owner-scoped status, and resumable uploads. Support --print and --debug.
• Add home-config commands, an unprivileged Docker image, updated OpenAPI contracts, architecture docs, and embedded assets. Schema migrates to v8; stop old processes before upgrading. Legacy commands remain compatible.
• Validated with mise run check (including 66 browser tests), the Go race suite, and Docker auth, container recreation, persistence, and replay checks.