# Session handoff — 2026-06-16 (73)

Short, focused handover. Continues from handoff-72 (which completed the
H2 hint-corpus verification pass). This session shipped one small
feature — a **`Ctrl-G` demo-mode alias for F1** — plus follow-on doc
hygiene. Commit `4016c3e`.

## §1. State

**Branch:** `main`, clean, all committed (local; **push pending** — your
step; the backlog now spans the CI merge, H2, the hint-corpus fixes,
handoffs 71/72/73, and this Ctrl-G commit). **2503 pass / 0 fail / 1
ignored** (the long-standing `friendly` doctest), **clippy clean**
(nursery, all targets). Open Gitea issues unchanged: **#35–#38**.

## §2. Why Ctrl-G (the problem)

Casts are recorded with **`autocast`** (ADR-0047 demo mode: `--demo` /
`RDBMS_PLAYGROUND_DEMO`). The contextual hint overlay (ADR-0053 / H2)
opens on **F1** — but F1 reaches the app only as a terminal **escape
sequence** (`\eOP` / `\e[11~`), and **autocast cannot emit escape
sequences**. So the single most teaching-relevant overlay was
unreachable in recordings (and in presenter/teacher sessions, which also
run `--demo`). Same wall that pushed step-captions onto `Ctrl+]` (a
single control byte) rather than `Ctrl+!`.

### Chord choice — why Ctrl-G, why not Ctrl-1

The user's first instinct was `Ctrl-1` (mnemonic, near F1). **Not
possible:** in a legacy terminal `Ctrl`+digit has no control byte —
`Ctrl-1` arrives as a bare `1` (would type "1" into the buffer). The
kitty keyboard protocol *would* encode it, but only as an escape
sequence (the very thing autocast can't send), and this app deliberately
does **not** push `KeyboardEnhancementFlags` (`runtime.rs` does only
`enable_raw_mode` + `EnterAlternateScreen`). So the usable space is
exactly **`Ctrl`+letter** (single legacy control bytes). After excluding
taken chords (`Ctrl-C` quit, `Ctrl-O` nav, `Ctrl+]` caption,
`Ctrl-A/E/W/K/U` readline per ADR-0049), byte-collisions
(`Ctrl-H/I/J/M/[`), flow-control (`Ctrl-S/Q`), and likely-future
(`Ctrl-R/P/N/Y/L/V`), **`Ctrl-G`** is the clean survivor (BEL/"abort" in
line editors — nothing destructive to shadow).

## §3. What shipped (commit `4016c3e`)

ADR-0047 **Amendment 1**. **In demo mode only**, `Ctrl-G` aliases F1:

- Runs the *exact* F1 hint logic (`hint_key` guard in
  `App::handle_key`, `src/app.rs` ~line 1226 — `key.code == F(1) ||
  (self.demo_mode && Ctrl-G)`), so live-input → form hint, empty input →
  recent-error / getting-started.
- **Badges as `[F1]`** (not `[CTRL-G]`): `demo_badge_label` maps
  `Ctrl-G → Some("[F1]")` (consulted only in demo mode — the caller
  gates). So a recorded cast is **visually identical to a real F1
  press**.
- **Demo-gated:** the shipped keymap stays F1-only. Outside demo mode
  `Ctrl-G` falls through to the inert catch-all (the `Char(c)` insert arm
  excludes CONTROL, so no `g` is typed).
- The keybinding strip (ADR-0051) is **not** changed — F1 stays the
  advertised key; `Ctrl-G` is a recorder aid and the badge already reads
  `[F1]`.

**Tests (test-first, `src/app.rs` Tier-1):** `ctrl_g_in_demo_mode_-
aliases_f1_on_input`, `…_on_empty_input`, `ctrl_g_outside_demo_mode_-
is_inert`, plus a `Ctrl-G → [F1]` assertion added to
`demo_badge_label_maps_the_invisible_keys`. All confirmed red→green; the
"inert" test passed on the pre-change code, proving the demo-gate.

### Using it in a cast
With `--demo` active, send **`Ctrl-G`** in the autocast script wherever
you want the hint overlay to appear; the viewer sees the `[F1]` badge.

## §4. Doc hygiene done alongside (same commit)

- **ADR-0047 file:** removed two stray `</content>` / `</invoke>` lines
  (tool-call residue accidentally committed when the ADR was authored).
- **CLAUDE.md "Things deliberately deferred":** dropped three **stale**
  entries — **I1b** readline shortcuts (done, ADR-0049), **I3** tab
  completion, and **I4** syntax highlighting (both done; requirements.md
  even carries a 2026-06-07 reconciliation note that I3/I4 were
  "shipped but marked not yet"). Only **I1** (multi-line input) remains —
  it is genuinely still open (`[ ]` in requirements.md). *(This follows
  the handoff-72 cleanup that removed the equally-stale m:n/C4 +
  project-storage entries.)*

## §5. Open / next (unchanged from handoff-72 §5)

The hint corpus is trustworthy and the cast-F1 gap is closed. Roadmap:

1. **Push** (your step).
2. **#35 (cargo fmt gate)** — precondition (CI merged) is met; the user
   wants it done once, before first publication. Needs a `rustfmt.toml`-
   vs-defaults decision first; tree is ~1800 hunks dirty.
3. Other open `requirements.md` items: **I1** multi-line input, **I5/B3**
   in-flight cancellation, **TT4** PTY tier-4 (unwired), **DOC1**/**E2**
   user docs (partial), **TT5** Windows-execution + Tier-4-in-CI, **D3**
   packaging manifests. Design-first (`[~]`): **V4** session journal,
   **TU1** tutorial, **C3a**, **V3**.
4. Hint follow-ups if wanted: **#36** `help` advanced-SQL, **#37** hint
   clause-concepts, **#38** hint diagnostic route.

## §6. How to take over

1. Read handoffs 71 → 72 → 73, `CLAUDE.md`, `docs/requirements.md`.
2. Confirm green: `cargo test` (**2503 / 1 ignored**) + `cargo clippy
   --all-targets` (clean).
3. For demo-mode / casting, read **ADR-0047** (+ its Amendment 1); for
   the hint overlay it aliases, **ADR-0053**.
4. Workflow unchanged: phased, test-first, `/runda` + DA before commits,
   ADR amendment + README index-upkeep for decided-area changes, confirm
   commit messages with the user.
5. Consider a `cargo sweep` at this milestone (`target/` grows; see
   CLAUDE.md "Build hygiene").