Merge colour-entry: Color Picker and Color panel keep typed values; colours read on a fixed scale (#323)

Conflict: crates/engine/src/cmd/style.rs: object.color params doc and enabled = next's (text?, has_text or selection) + the model form; apply_color = next's text targets and caret typing format + the branch's rounding-based swatch reuse
Conflict: crates/ui-egui/src/dialogs.rs: next's deleteCharacterStyle / swatchOptions arms; colorPicker = the branch's (no-op without edits, model-form colour) with next's `text`
Conflict: crates/ui-egui/src/panels/swatches.rs: double-click opens the picker with picker_fields + next's `text`; spectrum = the branch's model form + next's `text`
Conflict: docs/target-app-parity.md: the branch's Color panel line + next's Threading and Place text lines
Conflict: ROADMAP.md: logs both

docs/target-app-parity.md

@@ -295,7 +295,7 @@ It is evidence of breadth: each item exists. It is not a claim of InDesign-level
 - Graphics backend chosen before the window exists (DirectX 12 on Windows, Vulkan on Linux, Metal on macOS, OpenGL as the fallback; `WGPU_BACKEND` overrides) with a start-up fallback: a backend whose start never showed a frame is skipped at the next start and the status bar says so (`gpu.json`). Found on an AMD hybrid-graphics laptop whose Vulkan driver faulted at the first present.
 - Graphics adapter chosen by the app: the GPU that drives the primary display (Windows `EnumDisplayDevices`, Linux sysfs), then the power preference (`WGPU_POWER_PREF`, `WGPU_ADAPTER_NAME` override). An adapter that fails or hangs while the window starts is left out and the app starts again on the next one, then on the next backend, with software renderers last; wgpu's indirect-call check is off (it lost the Metal device on an Intel Mac, #334); why the app stopped is logged, also when the window never opened (#273). Ported from VectorCraft.
 - Edit › Paste Into (copied objects become a frame's content, clipped by it; rendered, PDF and IDML both ways — verified in InDesign 2026); Polygon Settings (sides, star inset; double-click the Polygon tool).
-- Color panel (fill/stroke proxy, CMYK/RGB/Lab sliders with channel ramps, tint slider for swatches, spectrum ramp, Add to Swatches) and Color Picker (double-click the proxy); mixed colours are unnamed (not listed in Swatches until added); `object.color`, `swatch.addToSwatches`, `swatch.addUnnamed`.
+- Color panel (fill/stroke proxy, CMYK/RGB/Lab sliders with channel ramps, tint slider for swatches, spectrum ramp, Add to Swatches) and Color Picker (double-click the proxy; R/G/B, C/M/Y/K and hex fields; a CMYK colour stays CMYK unless R/G/B values are typed); mixed colours are unnamed (not listed in Swatches until added); `object.color`, `swatch.addToSwatches`, `swatch.addUnnamed`.
 - Threading: click a selected text frame's in or out port (overset or not) to load the text cursor, then click a frame to thread it (stories merge), click empty space for a column-wide frame down to the bottom margin, or drag a frame; Shift-click autoflows, Alt-click stays loaded; click the linked frame or double-click a port to break the thread; Esc unloads. Link and unthread cursors show where a click threads or unthreads. `text.thread`, `text.unthread`, `text.removeFromThread`.
 - Place text files: Word (.docx: styles by name with their attributes, bold/italic/underline/size/font, footnotes, tables, tabs, breaks), RTF and plain text, into the insertion point, the selected frame or a new frame; autoflow threads one frame per page column and adds pages until the text fits; Remove Styles option (`designcraft-textimport`).
 - Gradient Feather (⇧G tool, `object.gradientFeather`): objects fade along a linear or radial opacity gradient, on screen and as a soft mask in PDF.