feat: add new OpenSpec skills for change management and onboarding

- Created `openspec-ff-change` skill for fast-forward artifact creation.
- Introduced `openspec-new-change` skill for structured change creation.
- Developed `openspec-onboard` skill for guided onboarding through OpenSpec workflow.
- Added `openspec-sync-specs` skill for syncing delta specs to main specs.
- Implemented `openspec-verify-change` skill for verifying implementation against change artifacts.
- Updated `.gitignore` to exclude OpenSpec generated files.
- Added `skills-lock.json` to manage skill dependencies.

.agents/skills/tailwindcss/references/layout-width.md

@@ -0,0 +1,102 @@
+---
+name: layout-width
+description: Setting element width with spacing scale, fractions, container sizes, and viewport units
+---
+
+# Width
+
+Utilities for setting the width of an element.
+
+## Usage
+
+### Spacing scale
+
+Use `w-<number>` utilities based on the spacing scale:
+
+```html
+<div class="w-24">w-24</div>
+<div class="w-48">w-48</div>
+<div class="w-64">w-64</div>
+```
+
+### Percentage widths
+
+Use `w-full` or `w-<fraction>` for percentage-based widths:
+
+```html
+<div class="flex">
+  <div class="w-1/2">50%</div>
+  <div class="w-1/2">50%</div>
+</div>
+<div class="flex">
+  <div class="w-2/5">40%</div>
+  <div class="w-3/5">60%</div>
+</div>
+<div class="w-full">100%</div>
+```
+
+### Container scale
+
+Use container size utilities like `w-sm`, `w-md`, `w-lg`:
+
+```html
+<div class="w-sm">Small container</div>
+<div class="w-md">Medium container</div>
+<div class="w-xl">Extra large container</div>
+```
+
+### Viewport units
+
+Use `w-screen` for full viewport width, or dynamic viewport units:
+
+```html
+<div class="w-screen">Full viewport width</div>
+<div class="w-dvw">Dynamic viewport width</div>
+<div class="w-svw">Small viewport width</div>
+<div class="w-lvw">Large viewport width</div>
+```
+
+### Content-based widths
+
+Use `w-auto`, `w-fit`, `w-min`, `w-max` for content-based sizing:
+
+```html
+<div class="w-auto">Auto width</div>
+<div class="w-fit">Fit content</div>
+<div class="w-min">Min content</div>
+<div class="w-max">Max content</div>
+```
+
+### Size utility
+
+Use `size-<number>` to set both width and height:
+
+```html
+<div class="size-16">16x16</div>
+<div class="size-24">24x24</div>
+<div class="size-full">100% x 100%</div>
+```
+
+### Custom values
+
+Use arbitrary values for custom widths:
+
+```html
+<div class="w-[117px]">Custom pixel width</div>
+<div class="w-[50%]">Custom percentage</div>
+<div class="w-[calc(100%-2rem)]">Custom calculation</div>
+```
+
+## Key Points
+
+- Spacing scale: `w-0` through `w-96` (and beyond)
+- Fractions: `w-1/2`, `w-1/3`, `w-2/3`, `w-1/4`, `w-3/4`, `w-1/5`, `w-4/5`, `w-1/6`, `w-5/6`
+- Container sizes: `w-3xs`, `w-2xs`, `w-xs`, `w-sm`, `w-md`, `w-lg`, `w-xl`, `w-2xl`, `w-3xl`, `w-4xl`, `w-5xl`, `w-6xl`, `w-7xl`
+- Viewport units: `w-screen` (100vw), `w-dvw`, `w-svw`, `w-lvw`
+- `size-*` utilities set both width and height simultaneously
+- Use `w-auto` to reset width at specific breakpoints
+
+<!--
+Source references:
+- https://tailwindcss.com/docs/width
+-->