fix(B-0272): accept hyphen-prefixed ROM option values

[AceHack]

Summary

• accept hyphen-prefixed values such as --datfile -set.dat and --dir -roms by treating only absent option values as missing
• return CLI argument parse errors through main() instead of calling process.exit inside parseArgs
• add a focused regression test for hyphen-prefixed datfile and directory values

Tests

• bun test tools/roms/canonicalize.test.ts
• git diff --check

Coordination

Follow-up to the merged #2166 review thread. This intentionally keeps the older claim/b0272-rom-canonical-naming-smallest-slice-2026-05-08 single-quote parser branch out of scope so it can be handled separately or retired deliberately.

[Copilot]

Pull request overview

Updates the ROM canonicalizer CLI to correctly accept option values that begin with - (e.g., --datfile -set.dat, --dir -roms) by treating only an actually-absent value as missing, and routes parse errors back through main() so the module is more testable and composable.

Changes:

• Adjust CLI arg parsing to accept hyphen-prefixed option values and propagate parse failures via main() return codes instead of process.exit inside parsing.
• Implement bounded-memory SHA1 hashing using a fixed-size read buffer rather than reading whole files at once.
• Add regression tests covering hyphen-prefixed values and clearer missing-value error reporting.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tools/roms/canonicalize.ts	CLI parsing behavior updated; hashing switched to streaming reads; small path handling tweak for rename targets.
tools/roms/canonicalize.test.ts	Adds focused CLI regression tests and updates scan expectations for extensionless/non-ROM files.
docs/backlog/P1/B-0272-atari-rom-canonical-naming-tosec-lookup-2026-05-08.md	Updates last_updated date for the backlog item.

Comments suppressed due to low confidence (1)

tools/roms/canonicalize.test.ts:22

• Test fixture MD5 value looks like 31 hex chars (MD5 should be 32). Even though the parser doesn’t validate MD5, keeping fixtures structurally valid avoids confusing future readers/debugging. Consider changing it to a 32-char hex string or omitting the md5 attribute entirely in the fixture.

  <game name="Combat (1977)(Atari)">
    <description>Combat (1977)(Atari)</description>
    <rom name="Combat (1977)(Atari).bin" size="2048" crc="4020b4fe" md5="b35e9442525e1a0b30dc0264c112233" sha1="da39a3ee5e6b4b0d3255bfef95601890afd80709" />
  </game>