docs(skills): drop stale AShard/EpochEndAccumulate references
The `crates/cardano/src/ashard/` module was merged into `crates/cardano/src/ewrap/` (it became EWRAP's per-shard leg) and the `EpochEndAccumulate` delta was renamed to `EWrapProgress`. The debug guide's tables, narrative, file-path references, and instrumentation hints still pointed at the old names and paths. Updates the Step 3 classification table, Step 5 work-unit narrative + source-file map, and Step 6 instrumentation table to: - talk about EWRAP/ESTART each having a per-shard leg + finalize, not a separate ASHARD work unit; - point at `ewrap/rewards.rs`, `crates/cardano/src/shard.rs`, and the per-unit `work_unit.rs` files; - reference `EWrapProgress` (not `EpochEndAccumulate`) and the `EpochWrapUpV2` / `EpochTransitionV2` deltas where boundary close / open is described. Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>