backport: assumeutxo M2 — EvoDB isolation and chainstate roles (bitcoin#25494, partial #27596)

[thepastaclaw]

Issue being fixed or feature implemented

This is milestone 2 of 7 in the stacked assumeutxo backport series, building on the snapshot-initialization groundwork merged in #7451. It introduces the chainstate roles and Dash-specific state separation needed for active snapshot and background validation chainstates to coexist safely.

What was done?

• Partially backported bitcoin#25494 by adding interfaces::BlockInfo, kernel::MakeBlockInfo, and the associated block-notification plumbing. The remaining index refactoring commits are intentionally excluded.
• Partially backported bitcoin#27596 by adding ChainstateRole. The remainder of that upstream assumeutxo PR stays in later milestones.
• Made EvoDB consistency markers and transactions chainstate-specific, with dual-chainstate restart and reorg coverage. Reads outside scoped transactions follow the active chainstate, while explicit background-validation transactions select the normal chainstate overlay.
• Removed persisted snapshot chainstates during explicit -reindex and -reindex-chainstate, restoring the normal chainstate before block import while continuing to require the snapshot EvoDB marker on normal startup.
• Bound Dash special-transaction and quorum processing to the chainstate performing validation instead of borrowing the active chainstate.
• Suppressed active-chain notifications from background validation while retaining BlockChecked behavior.
• Guarded masternode-list and quorum-history serving when requested endpoints or derived quorum work blocks are not locally available.
• Disabled DKG participation and quorum share production until snapshot background validation completes.
• Canonicalized serialization of block-derived EvoDB payloads.

The temporary M1 manager-rebuild workaround is not present. M2's structural ChainstateManager ownership makes that workaround, its test-only accessor, and its M1-specific regression test unnecessary.

How Has This Been Tested?

• Built the unit test binary with make -C src test/test_dash.
• Passed validation_chainstatemanager_tests, evo_db_tests, llmq_commitment_tests, llmq_snapshot_tests, evo_cbtx_tests, and miner_tests.
• Passed the whitespace, circular-dependency, include-guard, include-order, and file lints.
• Passed per-commit and cumulative git diff --check validation.
• Range-diffed the ten-commit restack against the previously reviewed M2 series. Original order and authorship are preserved; logical commits 3–6 and 8 contain the focused EvoDB, reindex, and unavailable-history corrections described above, while the remaining commits are patch-equivalent.

Breaking Changes

None. This remains unreleased assumeutxo groundwork; snapshot loading is introduced by a later milestone.

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have made corresponding changes to the documentation
• I have assigned this pull request to a milestone

[thepastaclaw]

CI diagnosis

These failures are unrelated to this PR's EvoDB/chainstate-role changes, so the branch is proper as-is and has not been modified:

• mac-build / Build source never reached the build step. Restore SDKs cache failed because depends-sdks-3b862087... was absent; the preceding cache job downloaded the SDK but GitHub denied saving it because its token had no writable cache scope.
• win64-build / Build source compiled successfully, then the shuffled unit suite page-faulted in validation_chainstate_tests/chainstate_update_tip at CreateAndActivateUTXOSnapshot(..., reset_chainstate=true). The PR does not modify src/test/validation_chainstate_tests.cpp, and a fresh rebuild of current develop (2406ebcb959) reproduces the same isolated crash at line 83.

Filed #7458 with the baseline reproduction and CI evidence. No commit, push, rebase, empty retrigger commit, or CI rerun was made for these unrelated failures.