apollo_batcher: refactor TaskTimer with a timer map per task label

[yoavGrs]

Extracts map_for_label and gives ReadPathsAndCommitBlock its own timer map
instead of aliasing the commit map.

Co-Authored-By: Claude Opus 4.8 (1M context) noreply@anthropic.com

[reviewable-StarkWare]

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[yoavGrs]

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• apollo_batcher: persist patricia proofs returned by the committer #14393
• apollo_batcher: route commitment through read_paths_and_commit_block under os_input #14392
• apollo_batcher: persist accessed keys before adding the commitment task #14391
• apollo_batcher: add ReadPathsAndCommitBlock committer task type #14385
• apollo_batcher: refactor commit metrics to read the label from the task output #14384
• apollo_batcher: refactor TaskTimer with a timer map per task label #14383 👈 (View in Graphite)
• apollo_storage: add patricia_proofs table for OS-input witnesses #14382
• main

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PR Summary

Low Risk
Observability-only timing refactor in commitment manager; no commit/revert behavior changes beyond correct per-label timer isolation.

Overview
Refactors TaskTimer so each CommitterRequestLabelValue uses its own per-block timer map, with shared lookup via a new map_for_label helper used by start_timer and stop_timer.

Under the os_input feature, ReadPathsAndCommitBlock no longer shares the commit map—it gets a dedicated read_paths_and_commit_block store—so timing for that path is tracked separately from ordinary CommitBlock work at the same height.

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