feat: implement reading orb id on Android

[alekseifedotov]

Read device id from /sys/devices/soc0/serial_number and save it as u32

Please use per-commit view for review

[github-actions]

• Blocking – Android build fails: orb_id_android.rs:27 combines Result<_, VarError> with Result<_, io::Error> via or_else; both async and blocking variants require the same error type. Convert the environment lookup explicitly and fall back with match.

• Blocking – non-Linux/Android targets fail: lib.rs:2 renamed orb_id.rs without providing a module path for macOS or other targets, so Rust looks for the now-missing orb_id.rs.

• Serde contract/test failure: orb_id_android.rs:12 derives externally tagged enum serialization ({"Mini":"abcd1234"}), while the existing contract and new test expect "abcd1234". Add serde(untagged) as in the Linux implementation.

[github-actions]

Blocking issues

• [P1] endpoints/src/lib.rs:19 — Removing the trailing / makes the next Url::join(suffix) replace the Orb ID segment. For example, .../orbs/ea2ea744 joined with status becomes .../orbs/status. Existing v1/v2 endpoint tests should fail. Keep format!("{orb_id}/").

• [P1] orb-info/src/orb_id_android.rs:1-3 — Async-only imports are unconditional. Building orb-info on Android with default-features = false, features = ["orb-id"] fails because crate::from_file and the optional futures dependency are unavailable. Gate these imports with #[cfg(feature = "async")].

[github-actions]

• [P0] endpoints/src/lib.rs:19 Preserve the trailing slash after orb_id. Without it, the second Url::join replaces the ID segment, producing paths such as /api/v2/orbs/status instead of /api/v2/orbs/<id>/status. Existing endpoint tests should fail.

• [P1] orb-info/src/orb_id_android.rs:9 Deriving Serialize for the u32 newtype emits Android IDs as JSON numbers. Callers changed from &str to &OrbId will therefore send {"orbId":1234} instead of the established {"orbId":"1234"}, affecting attest and speed-test backend requests. Implement string serialization consistently with Linux.

• [P1] orb-info/src/lib.rs:2 The original orb_id.rs was removed, but a replacement path is selected only for Linux and Android. Building orb-info with orb-id on macOS or other supported host targets now fails because Rust searches for the nonexistent orb_id.rs. Add a fallback or explicitly gate unsupported targets.

[github-actions]

• Blocker – endpoints/src/lib.rs:19: Removing the trailing / makes the following Url::join(suffix) replace the Orb-ID path segment. For example, .../orbs/ea2ea744 joined with status becomes .../orbs/status. Existing endpoint tests should fail. Preserve format!("{orb_id}/").

• Blocker – orb-info/src/orb_id_android.rs:9: Android OrbId derives numeric serialization, but these APIs previously serialized IDs as JSON strings. Challenge, proof, and speed-test requests will send 1234 instead of "1234", likely breaking backend contracts. Serialize/deserialize it as a string while retaining numeric parsing internally.

• Cross-platform regression – orb-info/src/lib.rs:2: orb_id.rs was renamed, but only Linux and Android receive replacement paths. Building orb-info with orb-id on macOS or other supported host platforms now fails because the default orb_id.rs no longer exists. Use the Linux implementation for all non-Android targets or retain a fallback module.

[github-actions]

• Blocker – endpoints/src/lib.rs:19: Removing the trailing / makes the subsequent join(suffix) replace the Orb ID path segment. For example, .../v1/1234 joined with auth becomes .../v1/auth, omitting the ID. Keep the trailing slash.

• Blocker – orb-info/src/orb_id_android.rs:9: Derived Serialize encodes Android IDs as JSON numbers, while existing API requests send IDs as strings. Calls such as remote_api.rs:262 will therefore change from {"orbId":"1234"} to {"orbId":1234} on Android. Implement string serialization and test the request payloads.

• Blocker – orb-info/src/lib.rs:2: On targets other than Linux or Android, neither path attribute applies, so Rust looks for the now-renamed orb_id.rs and compilation fails. Add an explicit fallback or restrict the module with an appropriate compile-time error.

[github-actions]

• orb-info/src/lib.rs:7: orb_id is now compiled even when the orb-id feature is disabled. On Linux this pulls in optional hex despite it not being enabled, breaking existing consumers such as ui that use orb-info with only orb-os-release. Add #[cfg(feature = "orb-id")] to the module declaration.

• orb-info/src/orb_id_android.rs:1: Android builds with orb-id but without async fail because from_file and futures are imported unconditionally, while both dependencies are gated behind async. Gate those imports with #[cfg(feature = "async")].

[github-actions]

• Blocking — orb-info/src/orb_id_android.rs:32: String::deserialize requires serde::Deserialize in scope. Android builds enabling serde will fail to compile. Use <String as serde::Deserialize>::deserialize(deserializer) or import the trait.

[github-actions]

• orb-info/src/orb_id_android.rs:52: Trim ORB_ID before parsing, as the Linux implementation does. Currently values such as "1234\n" fail on Android despite being accepted elsewhere; the sysfs fallback is already trimmed. The blocking path has the same issue at line 61.

[github-actions]

No concrete correctness, security, race-condition, or merge-blocking issues found in the PR changes.

[github-actions]

• orb-info/src/orb_id_android.rs:53 and :62: ORB_ID is parsed without trimming, unlike the Linux implementation and file fallback. Values such as "1234\n" now fail with ParseIntError. Apply .trim() before parsing and test both read paths.

[github-actions]

• [P2] Preserve non-Android host support — orb-info/src/lib.rs:1–10: The new compile_error! prevents macOS builds with orb-id enabled, including consumers such as orb-endpoints. Previously, ID parsing and environment-based reads worked there. Select the existing implementation for non-Android targets to avoid this regression.

Review covered all three commits. Tests were not run in the read-only environment.