Merge upstream/main into pr/cr3-variants

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

README.md

@@ -337,7 +337,7 @@ LightCraft is young and moving fast: **alpha**. **Where we honestly stand** (det
 | Import: Add in place / Copy / Move, rename and folder templates, devices, duplicate detection, watched folders; Local folder browsing | ✅ |
 | MCP server (headless or live app, persistent libraries), CLI, control channel | ✅ |
 | XMP sidecars (read/write, auto-write), reading `crs:` develop settings, preset files (`.lcpreset`, XMP presets) | ✅ |
-| Optics (distortion, vignetting, auto + manual CA, defringe, lens corrections embedded in DNG files and Panasonic / Leica RW2 / RWL distortion data), Geometry (transforms, Constrain Crop), Upright (Auto/Level/Vertical/Full/Guided) | ✅ · camera lens profiles (our own) ⬜ |
+| Optics (distortion, vignetting, auto + manual CA, defringe, lens corrections embedded in DNG files, Panasonic / Leica RW2 / RWL distortion data and Nikon Z 6II / Z 8 / Z f distortion data), Geometry (transforms, Constrain Crop), Upright (Auto/Level/Vertical/Full/Guided) | ✅ · camera lens profiles (our own) ⬜ |
 | Photo Merge: HDR (auto-align, deghost), Panorama (spherical/cylindrical/perspective, boundary warp, auto crop), HDR Panorama → DNG | ✅ |
 | GPU pipeline (wgpu compute, CPU-exact within 1/255), CPU fallback on device limits / errors | ✅ · WebGPU in the browser 🚧 |
 | AI: segmentation masks, AI denoise, super resolution, faces; video | 🚧 (see [gaps](docs/gaps.md)) |
@@ -370,6 +370,31 @@ per CPU, otherwise exhaust RAM before any test runs. GPU coverage is unchanged.
 `CARGO_PROFILE_DEV_DEBUG`, `CARGO_BUILD_JOBS` and `RUST_TEST_THREADS` settings
 override these defaults. Ordinary development commands keep their own settings.
 
+**Release builds on memory-constrained machines:** [#1196](https://github.com/storytold/lightcraft/issues/1196)
+reports Arch/AUR release-link OOM kills on a 16 GB machine when the desktop and CLI build concurrently
+with full debug information, thin LTO and one codegen unit. The CI defaults above do not apply to
+ordinary `cargo build --release`. Start with one job; two may be suitable if enough memory is available:
+
+```sh
+CARGO_BUILD_JOBS=1 cargo build --release -p lightcraft -p lightcraft-cli
+# Alternatively: CARGO_BUILD_JOBS=2 cargo build --release -p lightcraft -p lightcraft-cli
+```
+
+If a packaging environment enables full debug information or memory-heavy LTO settings, use
+command-local overrides for a lower-memory source build:
+
+```sh
+CARGO_BUILD_JOBS=1 CARGO_PROFILE_RELEASE_DEBUG=0 CARGO_PROFILE_RELEASE_LTO=false CARGO_PROFILE_RELEASE_CODEGEN_UNITS=16 cargo build --release -p lightcraft -p lightcraft-cli
+```
+
+These POSIX-shell assignments affect only this command, not global Cargo configuration or the
+repository's release profiles. Disabling LTO may change performance and binary size; disabling debug
+information reduces debugging detail. This is build guidance, not a guarantee that any machine has
+enough memory. Downstream packagers should serialize large binary builds and avoid full debug
+information combined with LTO and one codegen unit on low-memory builders. A PKGBUILD that exports
+its own profile settings can override inherited variables; adjust the packaging recipe locally or
+contact its maintainer rather than assuming an environment prefix on `makepkg` will take precedence.
+
 **Chinese and Japanese text** need the shared font repo, an optional build input (official releases always include it):
 
 ```sh
@@ -385,7 +410,9 @@ Language**; the choice applies immediately and persists. See [docs/localization.
 
 **Logs:** the desktop app writes its log to standard error and to `logs/lightcraft.log` in its settings folder
 (Linux `$XDG_CONFIG_HOME/lightcraft/logs/`, by default `~/.config/lightcraft/logs/`; macOS
-`~/Library/Application Support/LightCraft/logs/`; Windows `%APPDATA%\LightCraft\logs\`), never in the library. A
+`~/Library/Application Support/LightCraft/logs/`; Windows `%APPDATA%\LightCraft\logs\`), never in the library.
+**Portable mode:** a file named `portable.txt` (or `LightCraft.portable`) next to the executable moves the settings
+folder to `LightCraftData` beside it. A
 launch from a desktop menu or the Dock has no terminal, so attach this file to a bug report (**Help ▸ Open Log
 Folder** shows it in the file manager). Each start moves the
 previous log to `lightcraft.1.log` and that one to `lightcraft.2.log`, so the log of a run that crashed survives the