[enaboapps]

Mac keyboard predictions remained blank in TextEdit because the prediction subprocess could not resolve the system-wide focused Accessibility element. In the VM it consistently returned kAXErrorCannotComplete (-25204), despite AXIsProcessTrusted() returning true. The worker now resolves the foreground application's focused element and rejects foreground changes during discovery. Because the pipe-driven worker has no AppKit event loop, it also processes pending foreground notifications with a zero-duration run-loop pass before each PID query. Existing protected-field, context and acceptance validation remains in place.

Transferred debug bundles now prefer their bundled database, retaining the source-tree fallback for unbundled development. Previously they always referenced the build machine's absolute source path.

Closes #813.

Validation:

• Node 24: lint, 163 frontend tests, 5 script tests and production build passed.
• Rust 1.97.1: formatting, clippy with warnings denied, 488 unit tests (1 existing ignored), 7 config tests and doc tests passed.
• Added fake foreground-discovery tests for missing/invalid processes, focus changes and AX failures; file-based tests cover bundled, transferred, missing and development database resolution.
• Signed development build in the Mac VM: TextEdit I would like wa produced water/watching/walking/washington/war. One Select inserted ter once; subsequent next-word suggestions appeared, manual Next retained the same suggestions, and selecting and inserted it once. TextEdit retained focus. No new Accessibility permission was required. Temporary content-free diagnostics were removed from this change.
• Final reviewed build e69ae16: repeated the TextEdit prefix completion, closed the disposable document, and compared its saved bytes to exactly I would like water (including one trailing space): passed.
• Separate VM probe compared long-lived NSWorkspace readers: without event processing the PID stayed at Terminal; a zero-duration default-mode run-loop pass correctly observed Terminal → TextEdit → Terminal. The fix performs this pass before both foreground checks.
• Restored all three VM configuration files byte-for-byte, closed the task-owned documents, stopped test processes, and returned the VM to its prior suspended state. No permissions changed. Signed local Mac PID 55560 remained untouched; Windows VM was untouched.
• Independent latest-head review of e69ae16fd57a8c69056a427bdd3247f0b4805da9: no actionable findings. All latest-head CI checks passed, including Mac and Windows native tests and packaging, frontend, dependency audit and CodeQL.

This fixes ordinary Mac context-based predictions independently of the unmerged buffer fallback in #812. No merge or release is included.