feat: v2.5.4 — Query Explorer folded into Sessions, Windows picker and paths

- Sessions page tabs: Sessions · Events · Agents. QueryExplorer.tsx became
  AgentsTable.tsx (agents only — sessions and events already had tabs);
  /query redirects to /sessions?view=agents and leaves the sidebar.
  GET /api/query is unchanged and still answers all three entities.
- Windows picker opens in front: -EncodedCommand script spends the hidden
  first ShowWindow that windowsHide gives the process, then brings the TopMost
  owner forward via AttachThreadInput (v2.5.3's owner was itself hidden).
- Session page Resume/Fork/Open pane: owningLane and sessionWorktreeName
  match Windows folders (either separator), with a test.

server/__tests__/native-dialog.test.js

@@ -44,12 +44,17 @@ describe("native-dialog", () => {
     assert.ok(!args.slice(0, -2).join(" ").includes("shell script"));
   });
 
-  it("gives the Windows dialog a TopMost owner, so it does not open behind the browser", () => {
+  it("gives the Windows dialog a foreground TopMost owner, so it does not open behind the browser", () => {
     for (const kind of ["dir", "file"]) {
       const [[cmd, args]] = nd.dialogCommands(kind, "C:\\x", "win32");
       assert.equal(cmd, "powershell.exe");
-      const script = args.at(-1);
-      assert.match(script, /\$o\.TopMost = \$true;.*\$o\.Show\(\);.*\$d\.ShowDialog\(\$o\)/);
+      assert.equal(args.at(-2), "-EncodedCommand");
+      const script = Buffer.from(args.at(-1), "base64").toString("utf16le");
+      assert.match(
+        script,
+        /\$o\.TopMost = \$true;[\s\S]*ShowWindow\(\$o\.Handle, 1\)[\s\S]*\$o\.Show\(\)[\s\S]*Front\(\$o\.Handle\)[\s\S]*\$d\.ShowDialog\(\$o\)/
+      );
+      assert.match(script, /AttachThreadInput/);
       assert.ok(!script.includes("C:\\x"), "the folder travels in env, never the script");
     }
   });