feat(ongeki): make inGameID nullable and update seeds to 2026/02/19

[nyairobi]

Making inGameID nullable

#1425 introduced demand for seed parity with JP, and in order to achieve that I need to make inGameID optional, which causes a bit of a mess, as bonus tracks are currently defined as tracks in the ID range [7000, 8000) because I was too stingy about the isUnranked flag (now re-introduced as isBonusTrack). This is closer to the original impl which should have stayed like that.

Re:Fresh folders get screwed by this change, but older versions are complete so they can stay as they are. New folders have the same chart counts as old ones so everything seems alright I guess. I don't remember inGameID being needed for anything else.

One caveat is that the seed tester spams warnings Chart ID x (song ID y) cannot be matched using matchType=inGameID because its inGameID is unknown.

Seeds

• Updated seeds to 2026/02/19.
• Reformatted/fixed/updated all search terms.
• Added more tooling for automating future seeds.
• Added flavor genres to all relevant songs (BMS and some Ongeki originals); those are genres by the IIDX definition as opposed to the GCM definition (more info here). The data was cross-checked between wikiwiki, SilentBlue and Bokutachi's BMS seeds.

[tachi-repo-bot]

A commit has changed the seeds. View the diff here.

[nyairobi]

Since this is taking weeks, may as well push other changes.

[tachi-repo-bot]

A commit has changed the seeds. View the diff here.

[tachi-repo-bot]

A commit has changed the seeds. View the diff here.

[nyairobi]

A commit has changed the seeds. View the diff here.

[tachi-repo-bot]

A commit has changed the seeds. View the diff here.

[nyairobi]

Client tests are now failing because 6523282 is missing the "u" flag