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.

[github-actions]

• [P2] Preserve macOS support — orb-info/src/lib.rs:1–10: The new platform guard prevents previously portable consumers such as orb-endpoints from compiling or running native tests on macOS. Parsing IDs and using the ORB_ID override previously worked there without Orb hardware. Select the Android implementation specifically and retain the existing implementation for other supported hosts.

Tests could not run because the Rust toolchain attempted to write to the read-only filesystem.