refactor: convert prompt to skill format

Per reviewer feedback, migrate from prompts/ to skills/ format:
- Move prompt → skills/finnish-humanizer/SKILL.md with proper frontmatter
- Bundle references/patterns.md (26 AI patterns + 4 style markers)
- Regenerate README tables via npm start

docs/README.skills.md

@@ -35,6 +35,7 @@ Skills differ from other primitives by supporting bundled assets (scripts, code
 | [copilot-sdk](../skills/copilot-sdk/SKILL.md) | Build agentic applications with GitHub Copilot SDK. Use when embedding AI agents in apps, creating custom tools, implementing streaming responses, managing sessions, connecting to MCP servers, or creating custom agents. Triggers on Copilot SDK, GitHub SDK, agentic app, embed Copilot, programmable agent, MCP server, custom agent. | None |
 | [create-web-form](../skills/create-web-form/SKILL.md) | Create robust, accessible web forms with best practices for HTML structure, CSS styling, JavaScript interactivity, form validation, and server-side processing. Use when asked to "create a form", "build a web form", "add a contact form", "make a signup form", or when building any HTML form with data handling. Covers PHP and Python backends, MySQL database integration, REST APIs, XML data exchange, accessibility (ARIA), and progressive web apps. | `references/accessibility.md`<br />`references/aria-form-role.md`<br />`references/css-styling.md`<br />`references/form-basics.md`<br />`references/form-controls.md`<br />`references/form-data-handling.md`<br />`references/html-form-elements.md`<br />`references/html-form-example.md`<br />`references/hypertext-transfer-protocol.md`<br />`references/javascript.md`<br />`references/php-cookies.md`<br />`references/php-forms.md`<br />`references/php-json.md`<br />`references/php-mysql-database.md`<br />`references/progressive-web-app.md`<br />`references/python-as-web-framework.md`<br />`references/python-contact-form.md`<br />`references/python-flask-app.md`<br />`references/python-flask.md`<br />`references/security.md`<br />`references/styling-web-forms.md`<br />`references/web-api.md`<br />`references/web-performance.md`<br />`references/xml.md` |
 | [excalidraw-diagram-generator](../skills/excalidraw-diagram-generator/SKILL.md) | Generate Excalidraw diagrams from natural language descriptions. Use when asked to "create a diagram", "make a flowchart", "visualize a process", "draw a system architecture", "create a mind map", or "generate an Excalidraw file". Supports flowcharts, relationship diagrams, mind maps, and system architecture diagrams. Outputs .excalidraw JSON files that can be opened directly in Excalidraw. | `references/element-types.md`<br />`references/excalidraw-schema.md`<br />`scripts/.gitignore`<br />`scripts/README.md`<br />`scripts/add-arrow.py`<br />`scripts/add-icon-to-diagram.py`<br />`scripts/split-excalidraw-library.py`<br />`templates/business-flow-swimlane-template.excalidraw`<br />`templates/class-diagram-template.excalidraw`<br />`templates/data-flow-diagram-template.excalidraw`<br />`templates/er-diagram-template.excalidraw`<br />`templates/flowchart-template.excalidraw`<br />`templates/mindmap-template.excalidraw`<br />`templates/relationship-template.excalidraw`<br />`templates/sequence-diagram-template.excalidraw` |
+| [finnish-humanizer](../skills/finnish-humanizer/SKILL.md) | Detect and remove AI-generated markers from Finnish text, making it sound like a native Finnish speaker wrote it. Use when asked to "humanize", "naturalize", or "remove AI feel" from Finnish text, or when editing .md/.txt files containing Finnish content. Identifies 26 patterns (12 Finnish-specific + 14 universal) and 4 style markers. | `references/patterns.md` |
 | [gh-cli](../skills/gh-cli/SKILL.md) | GitHub CLI (gh) comprehensive reference for repositories, issues, pull requests, Actions, projects, releases, gists, codespaces, organizations, extensions, and all GitHub operations from the command line. | None |
 | [git-commit](../skills/git-commit/SKILL.md) | Execute git commit with conventional commit message analysis, intelligent staging, and message generation. Use when user asks to commit changes, create a git commit, or mentions "/commit". Supports: (1) Auto-detecting type and scope from changes, (2) Generating conventional commit messages from diff, (3) Interactive commit with optional type/scope/description overrides, (4) Intelligent file staging for logical grouping | None |
 | [github-issues](../skills/github-issues/SKILL.md) | Create, update, and manage GitHub issues using MCP tools. Use this skill when users want to create bug reports, feature requests, or task issues, update existing issues, add labels/assignees/milestones, or manage issue workflows. Triggers on requests like "create an issue", "file a bug", "request a feature", "update issue X", or any GitHub issue management task. | `references/templates.md` |