fix(inbox): show sent mail in the unified inbox + fix compose attach button

- inbox merges crm.mail.list threads (kind MAIL) into crm.inbox.list items so
  sent/received mail actually appears in the one surface; mail shows in the
  Open view (it has no inbox work-item state) and opens in MailReader on click.
  Mail rows are read/reply only — no Done/Snooze/Archive (crm.inbox.transition
  doesn't apply to a mail thread).
- compose Attachments block was wrapped in <Field> (a <label>), so the label
  hijacked the Attach button's click via label→file-input association and the
  picker misfired. Use a plain div with the same field styling.

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

src/components/dashboard/inbox.tsx

@@ -14,6 +14,7 @@ import { useInboxData, type InboxState, type UiInboxItem } from "@/lib/inbox-api
 import { MailReader, NewMailModal } from "./mail";
 
 const KIND_LABEL: Record<string, string> = {
+  MAIL: "Mail",
   MENTION: "Mention", NEEDS_REPLY: "Needs reply", NEEDS_REVIEW: "Needs review", NEEDS_APPROVAL: "Needs approval",
   SUPPORT_UPDATE: "Support", MEETING_FOLLOWUP: "Meeting", DIGEST: "Digest", SYSTEM_ALERT: "Alert", CRM_OWNER_INTEREST: "Owner",
 };
@@ -103,7 +104,7 @@ function ItemRow({ it, active, onClick }: { it: UiInboxItem; active: boolean; on
       }}
     >
       <span style={{ marginTop: 2, color: isMention ? "var(--orange)" : "var(--text-2)", flexShrink: 0 }}>
-        <Icon name={it.threadId ? "chat" : isMention ? "chat" : "bell"} size={18} />
+        <Icon name={it.kind === "MAIL" ? "mail" : it.threadId ? "chat" : isMention ? "chat" : "bell"} size={18} />
       </span>
       <div style={{ flex: 1, minWidth: 0 }}>
         <div style={{ display: "flex", gap: 6, alignItems: "center", flexWrap: "wrap" }}>
@@ -122,8 +123,9 @@ function Detail({ it, onError, onDone, onSnooze, onArchive }: {
 }) {
   return (
     <>
-      {/* Item actions bar (works for every item, threaded or not) */}
-      {it.state === "OPEN" && (
+      {/* Item actions bar — only for real inbox work-items. Mail isn't an inbox item
+          (no crm.inbox.transition), so it gets read/reply only, no Done/Snooze/Archive. */}
+      {it.state === "OPEN" && it.kind !== "MAIL" && (
         <div style={{ display: "flex", gap: 6, padding: "10px 16px", borderBottom: "1px solid var(--border)", justifyContent: "flex-end" }}>
           <Btn variant="ghost" icon="clock" onClick={onSnooze}>Snooze</Btn>
           <Btn variant="outline" icon="check" onClick={onDone}>Done</Btn>