style(web): fix prettier config, format entire web/ tree

.prettierrc.json was missing "semi": false, so prettier wanted to add
semicolons to a codebase written without them (763 semicolon-free
statements vs. 150 with, in hand-written .ts; zero hand-written .svelte
files use them at all). That's why prettier --check failed on 249 files
— not because the code was unformatted, but because the config didn't
match the actual house style. Added "semi": false; left printWidth/etc
as configured (printWidth barely moves the failure count: 218/213/212
files at 100/120/140).

Ran `prettier --write .` with the corrected config. Verified
semantics-preserving before and after:
- eslint: 142 problems both before and after, byte-identical
- build passes, 38/38 tests pass
- token-stream diff (whitespace/semicolons/quotes normalized) on all
  218 changed files: only 52 had any remaining token change, all either
  trailing-comma removal (matching trailingComma: "none") or import/
  ternary reflow — no semantic changes
- live smoke test: Knowledge, Tasks, Fleet map, and a chat window
  (AgentTrace, markdown, Scope graph, activity rail) all render
  correctly, no console errors

Most of the diff is shadcn/ui vendor files (lib/components/ui/) moving
from the CLI's own style (double quotes, tabs, semicolons) to house
style; re-running `shadcn-svelte add` on a component will need a
follow-up format pass.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/src/lib/components/desktop-shell/Desktop.svelte

@@ -45,7 +45,9 @@
   // field.
   function onWindowKeydown(e: KeyboardEvent) {
     const target = e.target as HTMLElement | null
-    const editable = !!target && (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA' || target.isContentEditable)
+    const editable =
+      !!target &&
+      (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA' || target.isContentEditable)
     if (editable) return
     if (!(e.metaKey || e.ctrlKey) || e.key.toLowerCase() !== 'z') return
     e.preventDefault()
@@ -84,7 +86,11 @@
 <div class="fixed inset-0 flex flex-col">
   <div class="relative min-h-0 flex-1 overflow-hidden" role="presentation">
     {#if bgActive}
-      <div class="pointer-events-none absolute inset-0 z-0 overflow-hidden" aria-hidden="true" style={bgOuterStyle}>
+      <div
+        class="pointer-events-none absolute inset-0 z-0 overflow-hidden"
+        aria-hidden="true"
+        style={bgOuterStyle}
+      >
         <div class="absolute" style={bgInnerStyle}></div>
       </div>
     {/if}
@@ -97,9 +103,7 @@
            old `currentTarget === target` event check. Left-click on bare
            desktop blurs the focused window (the familiar "click empty
            desktop to deselect" affordance). -->
-      <ContextMenu.Trigger
-        class="absolute inset-0 z-0"
-        onclick={() => wm.blur()}
+      <ContextMenu.Trigger class="absolute inset-0 z-0" onclick={() => wm.blur()}
       ></ContextMenu.Trigger>
       <ContextMenu.Content class="min-w-48">
         <ContextMenu.Item onSelect={() => wm.arrange('cascade')}>