feat: trezor hardware support

[coreyphillips]

Description

The intention of this Trezor dev dashboard is to serve as a place for developers to test and troubleshoot Trezor hardware features as they emerge. This is not meant to be user facing, but to serve as a reference for how to use and interact with Trezor hardware devices once work on user-facing Trezor features begin by native devs.

• Implements Trezor hardware support via USB and bluetooth
• Implements a Trezor dev dashboard that is only be accessible in dev mode at the following location:
  • Settings->Advanced->Trezor

Preview

QA Notes

• The latest bindings containing Trezor hardware support can be found here.
• If you require an apk please let me know and I can build and send one for testing.

[github-advanced-security]

detekt found more than 20 potential problems in the proposed changes. Check the Files changed tab for more details.

[jvsena42]

utAck

[ovitrif]

Review Pass 1 - Code

LGTM, nice code overall!

Compiled a list of nits which I will address in a stacked PR, nothing to worry about:

---

Critical Issues (3 found)

#	Agent	Issue	Location
1	code-reviewer	error() throws IllegalStateException instead of AppError	TrezorRepo.kt:370,380,420,515,521
2	code-reviewer	List used instead of ImmutableList in TrezorState (flows to composables)	TrezorRepo.kt:582-583
3	error-hunter	Missing .onFailure in autoReconnect — failure is completely silent, no toast, no log	TrezorViewModel.kt (autoReconnect call)

Important Issues (10 found)

#	Agent	Issue	Location
4	code-reviewer	Missing CHANGELOG entry for feat: PR	CHANGELOG.md
5	code-reviewer	Logger in serializer missing context = TAG and manually appends Throwable	TrezorDataSerializer.kt:18
6	code-reviewer	TrezorStore suspend functions not wrapped in withContext(ioDispatcher)	TrezorStore.kt:20-27
7	error-hunter	Bare runCatching in disconnect() / forgetDevice() — inner errors silently swallowed	TrezorRepo.kt:302,443-449
8	error-hunter	saveThpCredential verification detects failure but only logs, doesn't propagate	TrezorTransport.kt (credential save)
9	error-hunter	composeTx — invalid feeRate guard returns without resetting isComposing, creating stuck UI	TrezorViewModel.kt:408
10	error-hunter	closeBleDevice always returns success = true even when close fails	TrezorTransport.kt
11	type-analyzer	KnownDevice.transportType is stringly-typed ("bluetooth"/"usb") — should be an enum	TrezorRepo.kt:592
12	type-analyzer	connectedDevice and connectedDeviceId are a split nullable pair — should be a single composite	TrezorRepo.kt:584-585
13	type-analyzer	TrezorDebugLog.lines uses List<String> flowing directly to composables — needs ImmutableList	TrezorDebugLog.kt:13

Suggestions (9 found)

#	Agent	Suggestion	Location
14	comment-analyzer	~14 comments on private functions/fields should be removed per CLAUDE.md	TrezorTransport.kt (various)
15	comment-analyzer	callMessage comment contains temporal "now" — will rot	TrezorTransport.kt:275
16	comment-analyzer	Hardcoded "60 seconds" in comment will diverge from constant	TrezorTransport.kt:514
17	type-analyzer	SendStep enum should be a sealed interface with associated data (eliminates impossible states)	TrezorViewModel.kt:597
18	type-analyzer	TrezorUiState is a 27-field god object — consider splitting into sub-states	TrezorViewModel.kt:567
19	type-analyzer	Derivation path computed via string interpolation in 3 places — extract helper	TrezorViewModel.kt
20	type-analyzer	KnownDevice missing @Immutable annotation	TrezorRepo.kt:592
21	error-hunter	onConnectionStateChange ignores GATT error status parameter	TrezorTransport.kt:1003-1025
22	error-hunter	getPairingCode() returns empty string for timeout, cancellation, and interruption — ambiguous	TrezorTransport.kt:284-321

Test Coverage Gaps (8 critical gaps)

Priority	Gap	Criticality
1	connectWithThpRetry retry logic untested	9/10
2	autoReconnect all branches untested	9/10
3	connectKnownDevice untested	8/10
4	forgetDevice (security-relevant cleanup) untested	8/10
5	ensureConnected reconnection path untested	8/10
6	composeTx / signComposedTx validation untested	7/10
7	scan known-device filtering untested	7/10
8	connect persistence verification missing	7/10

Strengths

• Architecture follows established patterns well (repo, service, MVVM, DI)
• Proper use of Result API in the repo layer
• Screen composables correctly split into parent + Content()
• Good test infrastructure following project conventions
• TrezorTransport has thorough USB error handling with specific messages
• Hardware-specific "why" comments in TrezorTransport (BLE timing, GATT write type, etc.) are valuable
• UI section files have zero comments — appropriate and clean
• TrezorDebugLog has good bounded-size invariant enforcement
• Preview data is well-organized with realistic fixtures