Blockstream Jade

This commit hardens the firmware signing script used when releasing Blockstream Jade hardware wallet firmware. It adds `set -e` so the script stops immediately if any command fails, and explicitly checks that the public and private key files exist before proceeding. Without these changes, the script could silently continue past errors (for example, if a key file was missing or a signing command failed), potentially producing or releasing firmware that was not properly signed. Proper signing is important because users rely on firmware signatures to verify that the software running on their device is authentic and has not been tampered with.

This commit adds a new build helper script that signs production firmware files with a private key during release testing. It does not change any device code, cryptographic checks, or user-facing behavior. It is purely a release-engineering convenience script.

This commit only fixes spelling mistakes inside code comments (for example, changing 'sufficent' to 'sufficient' and 'Explcitly' to 'Explicitly'). No actual program instructions were changed, so it cannot affect security or functionality.

This commit is a housekeeping rework of the project's continuous-integration (CI) build and test pipeline. It renames build stages, splits the GitLab CI configuration into smaller files, generates CI test configurations from developer configs, removes a substitute test device, and adds a release-staging script. There is no change to the wallet firmware's security logic, cryptography, or user-facing behavior.

This commit is a code cleanup in the user-interface layer of the Blockstream Jade hardware wallet. It removes repeated 'if timeout' checks around button-waiting loops and lets the shared helper handle the timeout case instead. The commit message explicitly says there are no functional changes, and the diff shows only structural simplification—no security-sensitive logic was altered.

This commit is a code cleanup: it pulls the logic for waiting on a button press into a single shared helper function so the same code isn't repeated in many places. The behavior is essentially unchanged. The only functional difference is that one screen (the mnemonic setup) now explicitly treats a timeout as an error in normal builds, whereas before it would have hit a generic assertion. This is a minor hardening improvement, not a security vulnerability.

This commit is a straightforward internal cleanup of the user-interface drawing code for the Blockstream Jade hardware wallet. It changes how solid-color background boxes (called 'fill nodes') are created so callers can specify a fill style and parent container in one function call instead of two. There is no indication this fixes or introduces any security issue.

This commit only fixes three spelling mistakes in code comments within a single source file. No program logic, variables, or security behavior was changed.