fix: keep native code index current with official upstream main

[hannesrudolph]

What Problem This Solves

Fixes a scheduled native code index reporting unchanged indefinitely when its source development checkout stays pinned while official upstream main advances.

User Impact

The isolated native code producer follows official OpenClaw main using its own bare Git cache. Each published snapshot contains exact bytes from one captured commit and reports clean commit provenance. Serving and development worktrees are untouched.

Why This Change Was Made

A commit-only scanner reads bounded Git blobs directly, verifies their object identities, and retains the existing text limits. The existing native handoff publishes metadata and documents atomically; fetch, validation or write failure preserves the previous generation. Per-run receipts record upstream commit/tree and observation time. Code table schemas, owner controls, cadence and source-capture holds remain unchanged.

Evidence

• Synthetic Git tests cover dirty worktrees, moving HEAD, rename/delete, bare repositories, skipped file modes/binary/large blobs, input limits, cancellation and replacement refs.
• Ten Python cache/lifecycle tests passed, including failed fetch, interrupted initialization, wrong-source refusal, no-op and owner restoration.
• Native writer tests verify atomic rollback, obsolete replacement, no migration/permission change, FULL and both Darwin flush flags on the actual writable connection.
• An actual synthetic CLI test advances main after preparation and proves the captured commit is published; an injected write failure preserves the previous generation.
• Exact review is clean after making the isolated writer durability explicit; the old writer fails the Darwin flush negative control and the corrected writer passes with no separate driver hook.
• Installed signed producer published native snapshot 6 at commit d0cd39e4ef2b4f1ffd91a74586958b9833ada3e7: 54,746 documents / 520,792,748 bytes, dirty=false. All document metadata match a fresh scan of that same commit; a public added file matches exact Git blob bytes, and an obsolete path/ID is absent.
• Same-commit no-op passed without changing the core PID. Ordinary collection resumed with a successful post-handoff receipt.

[clawsweeper]

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