Fix code quality violations for publish

Remove unused blade settings pages not linked from UI
Convert remaining frontend pages to SPA actions
Convert settings user_settings and general to SPA actions
Convert settings profile pages to SPA actions
Convert contacts and projects add/edit pages to SPA actions
Convert clients add/edit page to SPA action with loading pattern
Refactor component scoped IDs from $id to $sid
Fix jqhtml comment syntax and implement universal error component system
Update all application code to use new unified error system
Remove all backwards compatibility - unified error system complete
Phase 5: Remove old response classes
Phase 3-4: Ajax response handler sends new format, old helpers deprecated
Phase 2: Add client-side unified error foundation
Phase 1: Add server-side unified error foundation
Add unified Ajax error response system with constants

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

node_modules/@jqhtml/vscode-extension/LLM_REFERENCE.md

@@ -117,7 +117,7 @@ Future versions may include:
 
 ### Component Usage
 ```jqhtml
-<MyComponent $id="instance" @click="handleClick">
+<MyComponent $sid="instance" @click="handleClick">
   <#slot>Content here</#slot>
 </MyComponent>
 ```
@@ -125,7 +125,7 @@ Future versions may include:
 ### Control Flow
 ```jqhtml
 <% for (let item of this.data.items): %>
-  <div $id="item_<%= item.id %>">
+  <div $sid="item_<%= item.id %>">
     <%= item.name %>
   </div>
 <% endfor; %>