📊 telemetry: cycle-consistent per-miner attribution for the dashboard

[george-connito]

Additive only — no changes to evaluation, scoring, or weights. The subnet-api-gateway feature-detects these metrics, so deploy order is free in both directions.

New per-miner families (miner_uid-labeled, set from finalize):

• validator_miner_last_scored_round_id — round_id of the last finalize verdict (scored / tie-zeroed / validation-failed / freeze-zero).
• validator_miner_round_delta — raw (baseline − val_loss)^1.2 signal for evaluated uids; distinct from score_latest (finalized podium score) so the dashboard can show "how close was I" for non-podium miners.
• validator_miner_evaluated_commit_info{hf_repo_id, hf_revision} — valued with the freeze round_id; strictly ≤1 labelset per uid (previous labelset evicted under a lock on commit change; KeyError-guarded for the post-restart case).

Emission moved INTO finalize_round_scores (after the journal flip): score snapshots (latest/avg/samples/emitted_at) now publish for EVERY verdict uid, not just weight recipients (~1 uid before), and the journal-recovery replay re-publishes everything after a restart — closing the "restart blanks the dashboard until the next full round" gap observed live during the 2026-07-23 cycle-api outage. The redundant snapshot loop in run.py's weight block is removed (WEIGHT_SUBMITTED stays).

RoundJournal bumped to v2: adds uid_to_commit (uid -> (hf_repo_id, hf_revision)) captured from uid_to_chain_checkpoint at freeze/finalize; v1 files still load (empty map); future versions rejected. _RecoveryRound hydrates checkpoint stubs so recovered finalizes emit commit info too.

Per-round series eviction: round_id label values emitted on validator_round_lifecycle_step / _miners_pending / _scored / _failed / bg_eval_lock_leak_total are tracked in-process and evicted via evict_round_series_before() on run.py's existing journal-prune cutoff — previously every round leaked permanent series.

Tests: 11 new (eviction invariant incl. restart simulation, journal v2/v1/future-version handling, finalize emission on live-shaped and recovery rounds, round-series eviction); full related suite (36) green in the staging image.