fix: enable enforce-canonical-classes tailwind lint rule (#9427)

## Summary

Enable `better-tailwindcss/enforce-canonical-classes` lint rule and
auto-fix all 611 violations across 173 files. Stacked on #9417.

## Changes

- **What**: Simplify Tailwind classes to canonical forms via `eslint
--fix`:
  - `h-X w-X` → `size-X`
  - `overflow-x-hidden overflow-y-hidden` → `overflow-hidden`
  - and other canonical simplifications
- Enable `enforce-canonical-classes` as `'error'` in eslint config

## Review Focus

Mechanical auto-fix PR — all changes produced by `eslint --fix`. No
visual or behavioral changes; canonical forms are functionally
identical.

**Stack:** #9417 → **this PR** → PR 3 (class order)

Fixes #9300 (partial — 2 of 3 rules)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9427-fix-enable-enforce-canonical-classes-tailwind-lint-rule-31a6d73d365081a49340d7d4640ede45)
by [Unito](https://www.unito.io)

src/platform/workspace/auth/WorkspaceAuthGate.vue

@@ -2,7 +2,7 @@
   <slot v-if="isReady" />
   <div
     v-else
-    class="fixed inset-0 z-[1100] flex items-center justify-center bg-[var(--p-mask-background)]"
+    class="fixed inset-0 z-1100 flex items-center justify-center bg-(--p-mask-background)"
   >
     <Loader size="lg" class="text-white" />
   </div>