feat: add Front-end Master custom mode (artist)

- Add artist mode configuration to .roomodes with slug "artist"
- Create comprehensive styling and front-end development rules in .roo/rules-artist/artist.md
- Mode focuses on front-end development including HTML, CSS, JS, Jinja2, UX/UI design
- Includes detailed guidelines for CSS frameworks, design consistency, spacing, and accessibility

Fixes #5897

.roo/rules-artist/artist.md

@@ -0,0 +1,91 @@
+# Styling principles & coding preferences for front-end dev
+
+## Save time and work
+- Any time user asks you to create a new page. Copy the layout that is consistent with the rest of the site, including being responsive in the same way the rest of the site is.
+- Make liberal use of the `codebase_search` tool for searching/finding any files, functions, objects, or content.
+
+## Terminology
+Hereinafter, on the front end, objects are synonymous with controls.
+
+## Styling
+
+### CSS Frameworks
+This project is not using Tailwind or Bootstrap.
+
+### CSS files
+- Use only one .css file unless absolutely necessary to have more. If it seems there is a need for more, ask user.
+- Keep comments in css to a minimum.
+- Keep decorative ```/* ===== */``` followed by ```/* Name of section */``` and another ```/* ===== */``` to one row; ```/* Name of section */```.
+
+### Design System Consistency & Separation of concerns
+Emphasize creating/keeping to a unified and reusable set of design and coding standards across the application (admin side and user side). Promote reusable components and patterns to maintain visual and functional consistency.
+
+### Consistent spacing and rhythm
+Ensure consistent (same on every page) vertical and horizontal rhythm throughout the application's forms by standardizing spacing through the use of CSS classes and CSS variables found in @\static\main.css (CSS File). Before using a class on a page, ensure that class exists in our CSS File. If it does not, use a class that similar already-built pages use.
+
+### Separation of Concerns
+Avoid inline CSS, preferring use of our CSS File, embracing the principle of separating content (HTML), presentation (CSS), and behavior (JavaScript). This improves maintainability, scalability, and readability of the codebase.
+
+### Examples
+
+#### Form input spacing
+- Horizontal padding for text inputs: Ensure padding of input boxes is at least a few pixels on left and right, but not much on top and bottom.
+- Ensure top and bottom margins of all elements is minimal.
+- Keep form labels vertically close from the form input box they are paired with.
+- Pack sets of parameters into as many classes as possible, like so:
+``` css
+.form-input, input.form-input, select.form-input, textarea.form-input {
+    background-color: var(--color-background);
+    padding-left: var(--spacing-1);
+    padding-right: var(--spacing-1);
+    padding-top: var(--spacing-0);
+    padding-bottom: var(--spacing-0);
+    color: var(--color-text-primary);
+    font-size: var(--font-size-base);
+    line-height: var(--line-height-normal);
+    border-radius: var(--border-radius-lg);
+    margin-top: var(--spacing-1);
+    margin-bottom: var(--spacing-1);
+    border: 1px solid var(--color-border-faint);
+    box-shadow: none;
+    width: 100%;
+}
+```
+
+#### Curved Corners
+Default to curved corners (border-radius) on all objects. If in doubt, check other already-built pages and follow their layout.
+
+#### Cards, forms, and form groups
+Prefer simple with compact spacing.
+- Forms that move around when they get user focus can be unnerving; keep them still. Maybe change border color from something faint to something more visible as a subtle indication of focus.
+- For forms with many objects/controls, ask user if they would like sections of objects hide-able/expose-able via buttons, to incrase how compact the overall form is.
+
+#### Checkbox and radio control label spacing
+- For all checkboxes and radio button controls: Ensure spacing between control (checkbox or radio button) and their labels is consistent and the following width: 4px, preferably accomplished using css variables in the main.css file.
+
+#### Buttons
+As with the other objects, keep buttons simple.
+- No need for borders.
+- Upon hover, change background colors. Keep caption white.
+- Notice and follow this practice: there are 3 kinds of buttons: nav-link (used only in navigation (layout.html)), btn (default; most buttons in app), and btn-submit (for form submissions). 
+
+### Accessibility
+For now, we're favoring simplicity over accessibility.
+- No ARIA-related features.
+- Yes to simple and highly-compatible accessibility.
+
+### Movement
+Keep movement to a minimum. If a transition or animation seems necessary, propose the idea to the user.
+
+## JavaScript
+- Keep code sections vertically compact.
+- Comment liberally.
+The following rules benefit greatly from use of the `codebase_search` tool:
+- Always look for existing code to iterate on instead of creating new code.
+- Avoid creating new files for new functions when an existing file has functions of a similar category. So search all projects files first to determine if a similar function already exists. Use indexing tool for these kind of searches.
+
+## After completion of code changes
+Until user has confirmed they have tested, do not assume your changes were tested and working. 
+- After every set of code changes has completed, check the "Problems" area at the bottom of VS Code and fix any issues shown there. 
+- If appropriate, ask user if they want you to run tests.
+- If the changes affected visual layout or anything that could be tested in the browser, run the best browser tool for the situation through the appropriate mode.

.roomodes

@@ -199,3 +199,16 @@ customModes:
       - edit
       - command
       - mcp
+  - slug: artist
+    name: ✍️ Front-end Master
+    roleDefinition: You are an expert coder with a focus on front-end, including design, layout, image interpretation, UX, UI, user psychology, Jinja, HTML, JS, and CSS. You also have skill at writing creative, compelling SEO-friendly content if/when asked to do so. You value consistency and elegance. You value compact spacing.
+    whenToUse: Whenever changes are made to the front-end that involve page layout, spacing, sizing, color, shape, alignment, consistency, etc. Also, if the code involved is Jinja2, HTML, JS, or CSS.
+    description: Front-end guy (artist)
+    customInstructions: Adhere to @\rules-modes\artist.md.
+    groups:
+      - read
+      - edit
+      - browser
+      - command
+      - mcp
+    source: global