Bring the README's features and standing up to 0.19.0

The develop paragraph counted eighteen operations fused into one
dispatch, before the view transform made nineteen and a detail stage
made the fusion two passes, and said nothing of editing on the scene
with Tone Mapping last. Presets are now a menu on the tool rail, a
panorama frame can be left out, and a linear DNG larger than one
texture develops. The requirement count and coverage are
traceability.md's (193, 85.5%), and tiled rendering is no longer
wholly unbuilt. outstanding.md gains its sweep note for 0.19.0 and
says in §11 what the frame choice changed.

README.md

@@ -25,26 +25,34 @@ dated folder and a backup beside it — is found, proved the same, and folded
 onto one copy with the spares in the trash. Face detection and identity,
 with the index syncing between devices.
 
-**Developing.** Eighteen declared operations fused into one compute
-dispatch, plus the neighbourhood work that cannot be: clarity, texture,
-capture sharpening, noise reduction, lens correction, spectral film
-simulation. Crop, straighten and correct converging verticals, spot repair,
-and local adjustments over masks the model draws — click a subject or a
-category, then paint, subtract a gradient or keep only where two selections
-agree, grow or shrink the edge. A mask's sliders add to the photograph's, the
-film's among them, so a sky can be burned in on the print as a darkroom
-printer would. Hot and dead photosites are mended before the demosaic, with
-nothing to set. Focus peaking and a raw histogram for judging
-what is recoverable. Presets, with a collection shipped in the application —
+**Developing.** Nineteen declared operations, those that read one pixel
+fused into a generated shader rather than run a pass each, plus the
+neighbourhood work that cannot be: clarity, texture, dehaze, capture
+sharpening, noise reduction, lens correction. Every edit works on the scene
+as the camera recorded it — linear, highlights beyond white included — and
+one `Tone Mapping` step, last, after sharpening and noise reduction, fits it
+to the screen, with a contrast and a white point of its own; a spectral film
+stock takes its place when one is chosen. Crop, straighten and correct
+converging verticals, spot repair, and local adjustments over masks the
+model draws — click a subject or a category, then paint, subtract a gradient
+or keep only where two selections agree, grow or shrink the edge. A mask's
+sliders add to the photograph's, the film's among them, so a sky can be
+burned in on the print as a darkroom printer would. Hot and dead photosites
+are mended before the demosaic, with nothing to set. Focus peaking and a raw
+histogram for judging what is recoverable. Presets, a click away in a menu
+at the foot of the tool rail, with a collection shipped in the application —
 everyday corrections, and a look for each measured colour, cinema and
 black-and-white stock — and Lightroom presets imported as looks that leave a
-photograph's own corrections alone. XMP sidecars other editors read.
+photograph's own corrections alone. XMP sidecars other editors read. A
+linear DNG larger than one GPU texture — a stitched panorama twenty thousand
+pixels wide — opens, develops and exports at full size.
 
 [![Segmenting an urban scene and choosing the sky as a mask](docs/manual/media/local-segment.png)](docs/manual/README.md#local-adjustments)
 
-**Panoramas.** Select the frames, align, choose a projection, fill the
-ragged border rather than crop it, and the composite lands beside its
-sources as a DNG, with a sidecar recording what it was merged from.
+**Panoramas.** Select the frames, align, untick any frame to leave it out
+and the rest re-align at once, choose a projection, fill the ragged border
+rather than crop it, and the composite lands beside its sources as a DNG,
+with a sidecar recording what it was merged from.
 
 [![Twelve hand-held frames aligned on a cylinder](docs/manual/media/panorama-aligned.png)](docs/manual/README.md#merging-a-panorama)
 
@@ -96,19 +104,19 @@ controls, its place in the chain and its tests.
 
 ## Where it stands
 
-**0.18.2**, twenty-eight tagged releases in. 192 numbered requirements in
-scope, 84% of them claimed by code and [traced to it](docs/dev/traceability.md);
+**0.18.2**, twenty-eight tagged releases in. 193 numbered requirements in
+scope, 85% of them claimed by code and [traced to it](docs/dev/traceability.md);
 the rest are written down rather than merely absent.
 
 **Not built:** plugins (post-v1, [D12](docs/dev/requirements.md)), compare and
-survey culling, AI denoise, tiled rendering, HDR merge and
-focus stacking, importing a Lightroom or darktable catalog, translations
-beyond the launch screen, most of the Android platform integration beyond
-running, and a Flatpak actually built and run in its sandbox. The
-performance targets are half verified: the per-commit benchmark suite §8
-requires exists for everything that does not need a frame — the catalog,
-the scan, the thumbnails — and not yet for the render path, so a regression
-there fails nothing.
+survey culling, AI denoise, tiled rendering beyond the export of an oversized
+DNG, HDR merge and focus stacking, importing a Lightroom or darktable catalog,
+translations beyond the launch screen, most of the Android platform
+integration beyond running, and a Flatpak actually built and run in its
+sandbox. The performance targets are half verified: the per-commit benchmark
+suite §8 requires exists for everything that does not need a frame — the
+catalog, the scan, the thumbnails — and not yet for the render path, so a
+regression there fails nothing.
 [outstanding.md](docs/dev/outstanding.md) is the list, with the reasoning for
 each.