polish(web): home + transcript bud-parity

- Home weather line: text-[13px]/#5f5f5f/leading-[19.5px] -> text-[16px]/#1b1b1b/leading-[24px]
  (bud's weather line spec).
- Transcript: inline code-chip bg near-black rgba(9,9,11,0.95) -> grey #f5f5f5 (bud renders
  code/value chips as light-grey chips; text inherits dark body color); user-message surface
  #efefef -> #f5f5f5 and tool-arg chip #f4f4f4 -> #f5f5f5 (bud's #f5f5f5 surfaces).

Author: iamjr15

apps/web/src/app/globals.css

@@ -384,7 +384,7 @@
   --thread-accent-purple-glow: rgba(248, 175, 44, 0.18);
 
   /* Thread Message Bubbles */
-  --thread-user-message-bg: #efefef;
+  --thread-user-message-bg: #f5f5f5;
   --thread-assistant-message-bg: #ffffff;
   --thread-assistant-message-border: #f1f1f1;
 
@@ -667,7 +667,7 @@
     padding: 0.2em 0.4em;
     font-size: 0.85em;
     font-family: var(--font-mono);
-    background-color: rgba(9, 9, 11, 0.95);
+    background-color: #f5f5f5;
     border-radius: 3px;
     word-break: break-word;
   }

apps/web/src/components/chat/message-parts.tsx

@@ -521,7 +521,7 @@ function ToolRow({ parts }: { parts: MessagePart[] }) {
         />
         <span className="shrink-0">{verb}</span>
         {arg ? (
-          <code className="truncate rounded bg-[#f4f4f4] px-1.5 py-0.5 font-mono text-[#1b1b1b] text-[12px]">
+          <code className="truncate rounded bg-[#f5f5f5] px-1.5 py-0.5 font-mono text-[#1b1b1b] text-[12px]">
             {arg}
           </code>
         ) : null}

apps/web/src/components/home/home-greeting.tsx

@@ -33,7 +33,7 @@ export function HomeGreeting() {
   }
   const clock = CLOCK_FORMATTER.format(now).replace(/\s+/g, "");
   return (
-    <p className="mt-4 text-center font-medium text-[#5f5f5f] text-[13px] leading-[19.5px]">
+    <p className="mt-4 text-center font-medium text-[#1b1b1b] text-[16px] leading-[24px]">
       {`${clock}${weatherSuffix(greeting ?? null)}`}
     </p>
   );