Diff: select match with highest similarity

[PremadeS]

Your checklist for this pull request

• I've read the guidelines for contributing to this repository.
• I made sure to follow the project's coding style.
• I've documented every RZ_API function and struct this PR changes.
• I've added tests that prove my changes are effective (required for changes to RZ_API).
• I've updated the Rizin book with the relevant information (if needed).
• I've used AI tools to generate fully or partially these code changes and I'm sure the changes are not copyrighted by somebody else.

Detailed description

When diffing two files where the fileB has multiple candidate functions that can be matched against a function in fileA, select the one with the highest similarity instead of one that appears last.

related to: rizinorg/cutter#3625
requires: rizinorg/rizin-testbins#312

Output before:

┌────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ name0                    │ size0 │      addr0 │ type     │ similarity │      addr1 │ size1 │ name1                         │
│────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────│
│ sym.imp.printf           │     6 │ 0x00001030 │ COMPLETE │ 1.000000   │ 0x00001030 │     6 │ sym.imp.printf                │
│ sym.imp.__cxa_finalize   │     6 │ 0x00001040 │ COMPLETE │ 1.000000   │ 0x00001040 │     6 │ sym.imp.__cxa_finalize        │
│ sym.deregister_tm_clones │    34 │ 0x00001080 │ COMPLETE │ 1.000000   │ 0x00001080 │    34 │ sym.deregister_tm_clones      │
│ sym.process_data         │    84 │ 0x00001139 │ PARTIAL  │ 0.500000   │ 0x00001190 │    50 │ sym.candidate_low_similarity  │
│                          │     0 │ ---------- │ UNLIKE   │ 0.000000   │ 0x00001139 │    87 │ sym.candidate_high_similarity │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Output after:

┌────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ name0                    │ size0 │      addr0 │ type     │ similarity │      addr1 │ size1 │ name1                         │
│────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────│
│ sym.imp.printf           │     6 │ 0x00001030 │ COMPLETE │ 1.000000   │ 0x00001030 │     6 │ sym.imp.printf                │
│ sym.imp.__cxa_finalize   │     6 │ 0x00001040 │ COMPLETE │ 1.000000   │ 0x00001040 │     6 │ sym.imp.__cxa_finalize        │
│ sym.deregister_tm_clones │    34 │ 0x00001080 │ COMPLETE │ 1.000000   │ 0x00001080 │    34 │ sym.deregister_tm_clones      │
│ sym.process_data         │    84 │ 0x00001139 │ PARTIAL  │ 0.965517   │ 0x00001139 │    87 │ sym.candidate_high_similarity │
│                          │     0 │ ---------- │ UNLIKE   │ 0.000000   │ 0x00001190 │    50 │ sym.candidate_low_similarity  │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Test plan

Run new test-case

rz-test test/db/tools/rz_diff

...

Closing issues

...

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 50.32%. Comparing base (e9157ca) to head (722fc34).
⚠️ Report is 1 commits behind head on dev.

Additional details and impacted files

Files with missing lines	Coverage Δ
librz/arch/similarity.c	55.58% <100.00%> (ø)

... and 15 files with indirect coverage changes

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