Wake Substrate post-#10404 hardening: idempotency + duplicate deduplication

Context

During the bidirectional smoke test of the wake substrate post-#10404 merge, Claude (@neo-opus-4-7) empirically discovered two distinct bugs in the wake infrastructure related to idempotency and duplicate deduplication.

Bug 1: Bootstrap Idempotency Miss

Calling manage_wake_subscription({action: 'bootstrap'}) when a subscription already exists for the tuple (agentIdentity, trigger, harnessTarget) should return status: 'existing' and avoid creating a duplicate. Instead, the action created a duplicate sub (e.g., WAKE_SUB:e5f96999 alongside existing WAKE_SUB:ca08d381) populated with the new template metadata.

Possible causes:

• The db.nodes.items iteration in WakeSubscriptionService.mjs:bootstrap failed to surface the old sub (potential cache miss).
• The trigger/harnessTarget shape on the old sub differs from the template post-load.
• Flawed tuple-matching logic.

Bug 2: Duplicate-Wake Delivery

A single A2A message (MESSAGE:626881c7) generated TWO wake notifications for the receiving agent, both citing the exact same subscription ID (Subscription: WAKE_SUB:ca08d381).

Possible causes:

• The Bridge daemon poll-loop iterates trace × sub pairs without strict per-(sub, trace) deduplication before osascript/prompt injection.
• The Coalescing engine flushed twice within the 30s window.
• add_message created two SENT_TO edges for the same MESSAGE id.

Proposed Solution

1. Idempotency Fix: Audit and patch WakeSubscriptionService.mjs:bootstrap to correctly identify existing subscriptions for the target tuple, preventing the generation of duplicate subscription nodes.
2. Deduplication Fix: Introduce a (sub, trace) deduplication map/set in bridge-daemon.mjs (or the coalescing logic) before invoking the hardware interrupt/wake script.

Note: The duplicate WAKE_SUB:ca08d381 is currently active and intentionally being kept alive by Claude (@neo-opus-4-7) for live-reproducible testing. Do not forcibly unsubscribe it until the fix is developed and validated against it.