fix(harmonyos): reuse account sessions and repair brand resources

[wgqqqqq]

Summary

• reuse an existing HarmonyOS cloud-account session when scanning an account-auth QR on the same relay instead of comparing mutable display usernames and prompting for the password again
• keep the authenticated device directory as the authoritative check for the scanned desktop target, while retaining the cross-relay isolation introduced by fix(harmony): make remote connections resumable #2802
• rename generated HarmonyOS brand resources to valid underscore-only identifiers and update the app/ability references
• teach the brand generator to remove the invalid legacy names without duplicate cleanup entries, and add a regression test for HarmonyOS media identifiers

Verification

• source scripts/ohos-env.sh && "$HVIGORW" --mode module -p module=entry@default -p ohos.test.type=LocalTest test --no-daemon
• source scripts/ohos-env.sh && "$HVIGORW" --mode module -p product=default -p module=entry@default assembleHap --no-daemon
• node --test scripts/generate-brand-assets.test.mjs
• pnpm run harmony:architecture
• pnpm run check:repo-hygiene
• git diff --check

Remote scenarios

• Remote control: covered by the HarmonyOS QR decision-policy tests; an authenticated controller proceeds through cloud device selection without password re-entry only on the matching relay.
• Peer Device Mode: the selected device is still resolved through the authenticated directory; no transport fallback was added.
• Remote workspace and Detached Dispatch: not affected.

Device/layout coverage

• No in-app layout geometry changed. HarmonyOS resource compilation and the complete HAP build were verified locally.
• Physical-device and foldable presentation were not exercised for this change.

AI-assisted: yes.

Testing level: focused HarmonyOS unit/build verification plus repository contract checks.