fix(qwen): dedupe slug variant root paths on case-insensitive filesystems

On macOS (case-insensitive HFS+), two slug variants differing only in
case resolve to the same projects directory, causing session files to be
read twice and inflating responseCount. Use realpathSync.native to
dedupe resolved root paths before walking.

Author: GCGH159

scripts/session-analysis/platforms/qwen.mjs

@@ -1,5 +1,6 @@
 #!/usr/bin/env node
 
+import { realpathSync } from "node:fs";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
 
@@ -315,8 +316,13 @@ export class QwenSessionAnalyzer extends SessionAnalyzer {
   async discoverSessions(scope, roots) {
     const sessions = new Map();
     const transcriptRoot = roots.find((root) => root.kind === "qwen-project-jsonl");
+    const seenRoots = new Set();
     for (const rootPath of transcriptRoot?.paths ?? []) {
       if (!await pathExists(rootPath)) continue;
+      let realRoot;
+      try { realRoot = realpathSync.native(rootPath); } catch { realRoot = path.resolve(rootPath); }
+      if (seenRoots.has(realRoot)) continue;
+      seenRoots.add(realRoot);
       const files = await walkFiles(rootPath, { maxDepth: 2, limit: 20_000, match: (file) => file.endsWith(".jsonl") });
       for (const filePath of files) {
         const probe = await probeTranscript(filePath, scope.workspace);