v1.2.6

1.2.6 - 2026-11-01

Numbers here describe the source in main. The release carries
Bench-1.2.6.g3a built by CI from this commit, and nobody has had it on a
calculator yet.

• The demo travels inside the add-in now: a .g3a is one file, so a folder
  cannot come with it, and "copy demo/notes into Bench/notes" was three steps
  on a PC before a new install had anything to look at. The ten demo files - the
  three notes, the three decks, the study log and the three formula booklets -
  are compiled into the add-in as C literals and written to the card on the first
  run, so a fresh install opens Notes, Cards, Study log and Formula book and
  finds something in every one. Rules: only files that are not there yet are
  written, so nothing you wrote is ever overwritten, and at most twelve files are
  written per run. The text is generated from demo/ and
  docs/samples/formulas/ by tools/gen_demo.py; make demo-check fails when
  the generated table and the sources drift apart, and tests/test_demo_data.c
  reads every entry back with the same checks (printable ASCII, len equal to
  the joined length, no duplicate, source file unchanged). One booklet is over
  the 4095 bytes ISO C promises for a string literal, so each file is a list of
  chunks the add-in joins before writing - the generator refuses anything over
  6144 bytes, the size store_write() takes. Unverified on device.
• The same demo is a separate download too: Bench-demo-1.2.6.zip holds
  Bench/notes, Bench/cards, Bench/study and Bench/formulas, so it
  extracts onto D:\ in USB Flash mode and lands exactly where the add-in
  writes. It is for a full card, a second card, or editing the notes on a PC
  before they ever reach the calculator. Built by tools/make_demo_zip.py,
  reproducible (sorted entries, fixed timestamps), checked in CI against the same
  sources, attached to the release and kept in dist/.
• store_exists(): the seeding needed a way to ask whether a file is there
  without reading it, so src/platform/store.{h,c} gained one (a BFile_Open
  in a world switch, closed immediately, no read). src/platform/demo.c is the
  only caller and never touches anything else.
• What this does not do: it does not touch a file that already exists, does
  not run anywhere but start-up, and does not write anything outside
  \fls0\Bench. A card that is full or write-protected still gets a working
  add-in, just without the demo - demo_install() ignores the failure.