Cherry-pick bmap file integrity check onto main and add test coverage

[Copilot]

Cherry-picked PR #50 commits onto latest main branch to maintain linear history as requested. This incorporates the integrity check feature with the latest dependency updates (thiserror 2.0.17, indicatif 0.18.2, nix 0.30.1, strum 0.27.2, quick-xml 0.38).

Changes

Cherry-picked from original PR #50:

• Add bmap checksum field: Added bmap_file_checksum field to Bmap struct and builder
• Bmap file integrity check: Implemented SHA256-based integrity verification for local bmap files
• Remote integrity check: Extended integrity check to remote bmap downloads

Additional improvements:

• Test coverage: Added 7 test cases in bmap-parser/tests/integrity.rs covering:

  • Valid checksums (signed files, unsigned files with all-zeros)
  • Invalid checksums (wrong hash, corrupted content, missing field)
  • Edge cases (whitespace handling)

• Deprecation fix: Removed deprecated .as_slice() calls in checksum calculation

  // Before
  let checksum = hex::encode(digest.as_slice());
  
  // After
  let checksum = hex::encode(digest);

• Merge conflict resolution: Resolved conflict in bmap-parser/src/bmap.rs where bmap_file_checksum() method needed to coexist with new total_mapped_size() documentation

All tests pass. Build completes without warnings. Linear commit history maintained.

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[sjoerdsimons]

@copilot It seems your changes didn't make it to the repository; rather then trying to rebase or merge; please cherry-pick and fix the patches instead so it's a linear history

[Copilot]

@copilot It seems your changes didn't make it to the repository; rather then trying to rebase or merge; please cherry-pick and fix the patches instead so it's a linear history

Cherry-picked the original commits onto main to create a linear history at 12a113f:

1. fd8e5af - Add bmap checksum field in Bmap struct
2. 28a5e35 - Bmap file integrity check
3. 0ad8bb8 - Remote Bmap file integrity check
4. 12a113f - Add comprehensive test cases and fix deprecation warning

All tests pass, no warnings. The commits are ready locally but need a force push to update the remote branch.