Fixing porter can strand parcels until daemon restart

[sergey3bv]

Should close #2120

[gemini-code-assist]

Summary of Changes

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This pull request addresses a bug where sweep parcels could become stranded in the chain porter if a failure occurred after the initial response was sent to the caller. It introduces a robust retry mechanism for specific post-delivery states and optimizes how sweeper-originated transactions interact with the porter to prevent unnecessary broadcasts.

Highlights

• Post-delivery failure recovery: Implemented a retry mechanism for recoverable post-delivery failures in the chain porter, allowing stranded parcels to be requeued with exponential backoff instead of requiring a daemon restart.
• Sweeper transaction optimization: Updated sweeper-originated channel transactions to skip redundant porter broadcasts while ensuring local addresses are still correctly imported.

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[gemini-code-assist]

Code Review

This pull request introduces a retry mechanism for the chain porter to handle recoverable post-delivery failures, such as those occurring during transaction confirmation or proof transfer. It also refactors the state machine to ensure local addresses are imported even when anchor transaction broadcasts are skipped. Review feedback highlighted a potential deadlock in the advanceState goroutine when handling background parcels with unbuffered error channels. Other improvements suggested include clearing retry bookkeeping upon permanent failure to prevent memory leaks and implementing a maximum retry limit to avoid infinite loops.