feat: make verify-merkle-proof more strict

[brice-stacks]

Checks for CVE-2012-2459 style variations in the tx-index or tx-count so that only the one pair of correct values will validate.

[coveralls]

Coverage Report for CI Build 26240722167

Coverage increased (+0.002%) to 85.961%

Details

• Coverage increased (+0.002%) from the base build.
• Patch coverage: 50 of 50 lines across 1 file are fully covered (100%).
• 6089 coverage regressions across 95 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

6089 previously-covered lines in 95 files lost coverage.

Top 10 Files by Coverage Loss	Lines Losing Coverage	Coverage
stackslib/src/chainstate/burn/db/sortdb.rs	628	90.24%
stackslib/src/config/mod.rs	344	69.31%
stackslib/src/chainstate/stacks/boot/mod.rs	248	94.21%
stackslib/src/chainstate/stacks/index/storage.rs	245	80.69%
clarity/src/vm/database/structures.rs	233	77.69%
stackslib/src/chainstate/stacks/miner.rs	224	83.5%
clarity/src/vm/database/clarity_db.rs	219	80.85%
stackslib/src/burnchains/burnchain.rs	216	71.23%
stackslib/src/chainstate/nakamoto/signer_set.rs	199	69.19%
stackslib/src/core/mempool.rs	170	86.84%

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Coverage Stats

Relevant Lines:	220546
Covered Lines:	189584
Line Coverage:	85.96%
Coverage Strength:	17824024.34 hits per line

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💛 - Coveralls