Compact the menu bar quota display

[makerjackie]

What changed

• replace the wide icon-plus-inline quota label with a compact two-line menu bar display
• make remaining percentage the large primary value
• show the reset distance as a smaller secondary line
• use monospaced digits to keep the percentage visually stable
• preserve the icon-only fallback when menu bar quota display is disabled or unavailable
• add an accessibility label/value and deterministic formatter tests
• bump the app to 0.8.4 (build 16)

User impact

Codex quota now occupies substantially less horizontal menu bar space while keeping the remaining percentage immediately scannable. Reset timing remains visible without competing with the primary value.

Validation

• ./test.sh
• git diff --check
• live visual capture of the installed signed build confirmed the two-line layout at macOS menu bar height