[topointon-jump]

We don't need this logic anymore 🎉

[github-actions]

 ┌─ ⚡ PERF · 7ee9eb1 vs main@d44b459 ─────────────────────────────────
 │ SUITE                               BASELINE          NEW         Δ
 │ replay tps, mainnet               13,473 tps   13,517 tps  ·  +0.32%
 │ bench tps, localnet              663,353 tps  668,071 tps  ·  +0.71%
 │ snapshot load, testnet                4.96 s       4.98 s  ·  +0.45%
+│ mem total, mainnet                150.28 GiB   150.28 GiB  ▼   0.00%
+│ mem total, testnet                 86.59 GiB    86.59 GiB  ▼   0.00%
 │ clean compile, firedancer             3.25 s       3.25 s  ·  +0.01%
 │ binary size, firedancer             57.94 MB     57.92 MB  ·  -0.03%
 ├─────────────────────────────────────────────────────────────────────
@@ 0 REGRESSIONS · 0 WARNINGS · 2 IMPROVED · 5 NOISE @@
 └─────────────────────────────────────────────────────────────────────

[Copilot]

🔵 Needs a closer look

Human review must confirm that supported deployments no longer require migration-epoch replay or reward recalculation before accepting these consensus-sensitive changes.

No open issues 🎉

What changed in this PR

This PR removes support for mixed Tower/Alpenglow migration-epoch rewards, simplifying reward calculation and epoch-credit handling across the validator, snapshots, and test harnesses.

Changes:

• Removes migration-specific reward calculations and marker metadata while retaining marker filtering on input.
• Simplifies snapshot and protobuf serialization to omit migration markers.
• Removes migration-specific unit tests and backtests.

File	Description
src/​flamenco/​stakes/​fd_stakes.c	Stops tracking migration-marker presence during credit extraction.
src/​flamenco/​runtime/​tests/​test_inflation_rewards.c	Removes migration reward tests and their helper.
src/​flamenco/​runtime/​tests/​run_backtest_ci.sh	Removes migration backtests from CI.
src/​flamenco/​runtime/​tests/​run_backtest_all.sh	Removes migration backtests from the full suite.
src/​flamenco/​runtime/​tests/​fd_svm_mini.c	Updates mock credits for the simplified structure.
src/​flamenco/​runtime/​tests/​fd_dump_pb.c	Removes migration-marker reconstruction from protobuf dumps.
src/​flamenco/​runtime/​tests/​fd_block_harness.c	Stops retaining marker metadata in the harness.
src/​flamenco/​rewards/​fd_rewards.c	Removes mixed-epoch reward calculation and recalculation branches.
src/​flamenco/​fd_flamenco_base.h	Removes marker metadata and its indexing helper.
src/​discof/​restore/​utils/​fd_ssload.c	Stops retaining marker metadata during snapshot restore.
src/​discof/​backup/​test_snap_roundtrip.c	Updates roundtrip tests to omit marker preservation.
src/​discof/​backup/​fd_ssmanifest_writer.c	Removes an unused epoch-schedule include.
src/​discof/​backup/​fd_ssmanifest_encoder.c	Removes migration-marker reconstruction from snapshots.

_{Review effort: Balanced}