Add unknown owner category to teams reports

[vanminh-grabtaxi]

Summary

Fix team size attribution so team reports account for unowned module/library contributors and APK-level others consistently.

Changes

• Include APK-level others in the synthetic app contributor for team reports.
• Preserve split APK identity for uncategorized APK files before storing them in a set, avoiding path-based de-duplication across split APKs.
• Report unmapped module/library contributors under NA instead of dropping them.
• Update docs to clarify:
  • APK-level uncategorized files go to synthetic app.
  • unmapped modules/libraries are reported as NA.
  • split APK entries with the same internal path are preserved for attribution.

Verification

• ./gradlew :app-sizer:test
• ./gradlew :cli:shadowJar
• sample/exec-cli.sh with Java 17

Fresh sample report validation:

device-1 others: apk=144,077, team=144,077, gap=0
device-2 others: apk=138,431, team=138,431, gap=0

All APK component rows now match team component rows in the sample reports.