feat(HAI-003): replace CreateTaskModal with inline card creation in Todo column

- Create InlineCreateCard component with auto-focused input, dependency
  dropdown, Enter to submit, Escape to cancel
- Update Column to render InlineCreateCard at top of Todo column body
- Update Board to pass through inline-create props to Todo column
- Update App to use isCreating state instead of createModalOpen
- Add CSS styles for inline create card, dependency dropdown
- Delete CreateTaskModal component

packages/dashboard/app/components/InlineCreateCard.tsx

@@ -0,0 +1,105 @@
+import { useState, useCallback, useEffect, useRef } from "react";
+import type { Task, TaskCreateInput } from "@hai/core";
+import type { ToastType } from "../hooks/useToast";
+
+interface InlineCreateCardProps {
+  tasks: Task[];
+  onSubmit: (input: TaskCreateInput) => Promise<Task>;
+  onCancel: () => void;
+  addToast: (msg: string, type?: ToastType) => void;
+}
+
+export function InlineCreateCard({ tasks, onSubmit, onCancel, addToast }: InlineCreateCardProps) {
+  const [description, setDescription] = useState("");
+  const [dependencies, setDependencies] = useState<string[]>([]);
+  const [showDeps, setShowDeps] = useState(false);
+  const [submitting, setSubmitting] = useState(false);
+  const inputRef = useRef<HTMLInputElement>(null);
+  const cardRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    inputRef.current?.focus();
+  }, []);
+
+  const handleKeyDown = useCallback(
+    async (e: React.KeyboardEvent) => {
+      if (e.key === "Escape") {
+        e.preventDefault();
+        onCancel();
+        return;
+      }
+      if (e.key === "Enter" && !e.shiftKey) {
+        e.preventDefault();
+        if (!description.trim() || submitting) return;
+        setSubmitting(true);
+        try {
+          const task = await onSubmit({
+            description: description.trim(),
+            column: "todo",
+            dependencies: dependencies.length ? dependencies : undefined,
+          });
+          addToast(`Created ${task.id}`, "success");
+        } catch (err: any) {
+          addToast(err.message, "error");
+        } finally {
+          setSubmitting(false);
+        }
+      }
+    },
+    [description, dependencies, submitting, onSubmit, onCancel, addToast],
+  );
+
+  const toggleDep = useCallback((id: string) => {
+    setDependencies((prev) =>
+      prev.includes(id) ? prev.filter((d) => d !== id) : [...prev, id],
+    );
+  }, []);
+
+  const truncate = (s: string, len: number) =>
+    s.length > len ? s.slice(0, len) + "…" : s;
+
+  return (
+    <div className="inline-create-card" ref={cardRef}>
+      <input
+        ref={inputRef}
+        type="text"
+        className="inline-create-input"
+        placeholder="What needs to be done?"
+        value={description}
+        onChange={(e) => setDescription(e.target.value)}
+        onKeyDown={handleKeyDown}
+        disabled={submitting}
+      />
+      <div className="inline-create-footer">
+        <div className="dep-trigger-wrap">
+          <button
+            type="button"
+            className="btn btn-sm dep-trigger"
+            onClick={() => setShowDeps((v) => !v)}
+          >
+            ⛓{dependencies.length > 0 ? ` ${dependencies.length} deps` : " Deps"}
+          </button>
+          {showDeps && (
+            <div className="dep-dropdown">
+              {tasks.length === 0 ? (
+                <div className="dep-dropdown-empty">No existing tasks</div>
+              ) : (
+                tasks.map((t) => (
+                  <div
+                    key={t.id}
+                    className={`dep-dropdown-item${dependencies.includes(t.id) ? " selected" : ""}`}
+                    onClick={() => toggleDep(t.id)}
+                  >
+                    <span className="dep-dropdown-id">{t.id}</span>
+                    <span className="dep-dropdown-title">{truncate(t.title, 30)}</span>
+                  </div>
+                ))
+              )}
+            </div>
+          )}
+        </div>
+        <span className="inline-create-hint">Enter to create · Esc to cancel</span>
+      </div>
+    </div>
+  );
+}