feat: introduce archify skill for generating architecture diagrams

- Added a new Archify skill, enabling users to create polished architecture, workflow, sequence, data-flow, and lifecycle diagrams.
- Implemented comprehensive functionality including rendering, validation, and delivery of diagrams in various formats.
- Integrated a user-friendly command-line interface for generating and previewing diagrams.
- Developed supporting files including package.json, LICENSE, and SKILL.md for documentation and licensing.
- Added unit tests to ensure reliability and functionality of the new skill.

These changes enhance the application by providing a structured approach to visualizing system architecture and workflows, improving user experience and data representation.

.agents/skills/archify/renderers/shared/desktop-readability.mjs

@@ -0,0 +1,26 @@
+export const DESKTOP_READABILITY_VIEWPORT = Object.freeze({ width: 1440, height: 900 });
+export const DESKTOP_READER_MIN_WIDTH = 960;
+export const DESKTOP_READER_HORIZONTAL_CHROME = 30;
+export const DESKTOP_READER_DIAGRAM_WIDTH = DESKTOP_READER_MIN_WIDTH - DESKTOP_READER_HORIZONTAL_CHROME;
+export const MIN_PROJECTED_NODE_TEXT_PX = 6;
+
+export function projectedNodeTextPx(sourceFontPx, viewBoxWidth, diagramWidth = DESKTOP_READER_DIAGRAM_WIDTH) {
+  if (![sourceFontPx, viewBoxWidth, diagramWidth].every(Number.isFinite) || viewBoxWidth <= 0 || diagramWidth <= 0) {
+    return Number.NaN;
+  }
+  return sourceFontPx * Math.min(1, diagramWidth / viewBoxWidth);
+}
+
+export function minimumReadableSourceTextPx(
+  viewBoxWidth,
+  diagramWidth = DESKTOP_READER_DIAGRAM_WIDTH,
+  minimumProjectedPx = MIN_PROJECTED_NODE_TEXT_PX,
+) {
+  if (![viewBoxWidth, diagramWidth, minimumProjectedPx].every(Number.isFinite)
+    || viewBoxWidth <= 0
+    || diagramWidth <= 0
+    || minimumProjectedPx <= 0) {
+    return Number.NaN;
+  }
+  return minimumProjectedPx / Math.min(1, diagramWidth / viewBoxWidth);
+}