reasampler/docs/COMPLETED.md

# COMPLETED.md — ReaSampler landed milestones

Completed milestone entries removed from `PLAN.md`. Each entry preserves its
original Goal, Verify, and checklist points with boxes marked done.

This file holds the current (1.x) cycle's landed milestones only. For all
pre-1.0 (version-0) history, see `docs/ARCHIVE.md`.

### Comment-reduction pass (tree-wide, twelve parallel tracks)

Cut source comment volume tree-wide: 209 files changed, net **−6,493** lines.
Comment-only lines went from 15,073 to ~8,671, a **~42% cut** — before the
pass, 37% of all source lines were comment-only. **Zero code drift**, verified
across all 209 files by comparing comment-stripped hashes; the sole
intentional exception (Daniel-approved) is two user-facing error strings in
`src/shell/capture/capture.cpp` that lost internal milestone IDs (`M8`, `M3`,
`M7+`). Build clean, 61/61 ctest pass. Code review surfaced 2 Major + 8 Minor
findings — all content cut that should have survived — and all ten were
remediated and re-gated before merge. Driver: Daniel's instruction — *"Brief
concise engineering comments. A little why, and maybe context, never WHAT."*

### Θ-W1-T1 — zone-retirement

ReaSampler 9000's zone-mapping system is retired: one loaded capture, one parameter
set, playing across the full keyboard repitched from root with key-tracking — no zones,
no per-zone divergence, no keymap of captures. The dedicated zone-editing face and its
authoring affordances (add/delete zone, per-zone parameter panel, Low/High/Root zone
legend) are gone; the root note survives as a first-class parameter. `sampler_core`
split along the note-routing/per-voice-render responsibility seam (no virtual `tick()`
on the per-voice path), and the Sample face split into chrome/waveform/decks bands with
a shared band-stack allocator, discharging the wave's two structural deliverables.
Migration adopts a saved multi-zone instance's first zone; single-zone instances lift
losslessly.

**Deviations from spec:**
- The key-range open question (**[propose]**) is answered outright rather than left
  open: no key-range concept survives at all — `KeyZone`/`lowNote`/`highNote` are gone
  from the engine, the write format, and the strip. A low/high pair remains re-addable
  later as two ordinary parameters. Θ-W2-T3 consumes this decision.
- **"Which zone is first" (**[verify]**) confirmed:** `PerformanceMap::zones` was an
  ordered vector and `Keymap::resolve` was first-match-in-order, so index 0 was the
  audible zone. Migration adopts index 0, and that zone's `sampleId` supersedes the
  envelope's stored `selectionId`.
- The control row (root strip, preview, velocity knob, curve button, Mono|Stereo) moved
  into the chrome band, directly under the title rather than above the deck —
  user-visible and deliberate; it's what makes Θ-W2's band-disjointness real.
- Loading a capture now clears the three capture-anchored overrides (root, loop span,
  start frame) while keeping the shaping parameters — strictly less destructive than the
  previous whole-zone drop.
- The embed strip became a read-only readout; it lost its click handler since with no
  zones there is nothing to select.
- **Migration side-effect:** a previously-zoned instance with implicit channel mode and
  a stereo capture persisted as Mono will reopen as **Stereo**. It converges on the
  documented rule and is reachable only for old blobs, but "sounds identical" was an
  acceptance bar, so it's a real deviation.
- `sampler_core.{h,cpp}`'s 956-line documented hot-path exception is retired, not
  relocated — the tree now carries no over-ceiling exception at all.
- `note_entry` was deleted as dead code (its only consumer was the removed zone editor).
- **Still unverified:** a real pre-change project reopening through REAPER's `setState`
  has not been exercised in the DAW; migration is proven only in the pure domain against
  hand-laid legacy bytes.

### Θ-W1-T2 — capture-handoff-bugs

Fixed both extension-side capture-handoff defects: drag-out now delivers the capture's
audio at the drop target every time (previously intermittent, retry-fixable); dropping a
capture onto an FX container now loads the instrument with the capture, matching the
FX-button drop path.

**Deviations from spec:**
- Item 5's root cause was three defects, not one: non-atomic COM refcounts racing a drop
  target's background copy; an unverified assumption that REAPER had already called
  `OleInitialize` on the calling thread; and a teardown-before-payload-check ordering bug
  that let an unresolvable payload consume the gesture.
- Item 6's fix rests on an unconfirmed hypothesis — that a bare `instantiate = -1` left
  placement to REAPER's ambient FX-chain insert point, which a container-focused chain
  window moves. It is now pinned to an explicit top-level position; nobody could confirm
  the mechanism without the DAW.
- The opportunistic rider was partly taken: `src/ingest.{h,cpp}` re-homed to
  `src/shell/actions/`. `ext_keys.h` was declined (most consumers sit in another track's
  exclusive surface); `resource.h` was declined (it's a build input paired with
  `src/resource.rc` and the SWELL resgen step).
- **Neither acceptance criterion has actually been met yet.** Item 5's gate is
  explicitly a soak ("a single pass is not a gate") and item 6 needs a live container
  drop; both require REAPER and are outstanding. The code is merged; the acceptance
  gates are not closed.