Add XML documentation for Dalvik.Bytecode

The `Dalvik.Bytecode` namespace contains **565** `To be added` placeholders in source XML documentation (excluding `docs\xml\index.xml`).

```powershell
rg -n -i --glob 'Dalvik.Bytecode/**' --glob 'ns-Dalvik.Bytecode.xml' 'to be added' docs\xml
```

## Update log

- 2026-09-10: Refreshed the placeholder scan from **579** to **565** (reduced by **14**). Related documentation PRs: [#461](https://github.com/dotnet/android-api-docs/pull/461), [#592](https://github.com/dotnet/android-api-docs/pull/592), [#644](https://github.com/dotnet/android-api-docs/pull/644).

Run the provided rg scan against docs\xml, limited to Dalvik.Bytecode/** and ns-Dalvik.Bytecode.xml, and inspect the matching source XML documentation entries. Replace the reported “To be added” placeholders with appropriate documentation, excluding docs\xml\index.xml. Done means the targeted scan no longer reports those placeholders.

索引モデルが issue の本文から書いたものです。