fix(claude): elide blocked-skill bundles on Windows paths — normalize backslashes before basename split

The text-block carrier's skill-dir basename used dir.split("/"), so Windows
clients (C:\Users\...\claude-api) never matched the blocklist and ~790K-char
bundles rode through to routed models (live incident 2026-07-15, ~297K-token
inputs). Normalize separators first (repo precedent: isOpencodexCatalogPath).
Tests: Windows/mixed/UNC elided, drive-relative pinned pass-through.

devlog: 260715_cross_platform_audit/010

Author: lidge-jun

src/claude/inbound.ts

@@ -180,7 +180,9 @@ function maybeElideSkillText(text: string, names: readonly string[]): string {
   if (!text.startsWith(SKILL_TEXT_MARKER)) return text;
   const firstLineEnd = text.indexOf("\n");
   const dir = text.slice(SKILL_TEXT_MARKER.length, firstLineEnd === -1 ? text.length : firstLineEnd).trim();
-  const base = dir.split("/").filter(Boolean).pop()?.toLowerCase() ?? "";
+  // Windows clients send `C:\Users\...\claude-api`; normalize separators before
+  // basenaming (repo precedent: src/codex/inject.ts isOpencodexCatalogPath).
+  const base = dir.replace(/\\/g, "/").split("/").filter(Boolean).pop()?.toLowerCase() ?? "";
   if (!names.includes(base)) return text;
   return `[opencodex] '${base}' skill document bundle (${text.length} chars) elided for routed models `
     + "(claudeCode.blockedSkills). The skill is loaded; answer from general knowledge instead of citing the bundle.";

tests/claude-inbound.test.ts

@@ -310,8 +310,9 @@ describe("bundled-skill elision for routed models (devlog 260712 060)", () => {
 
   // Live-capture carrier (2.1.207): the bundle rides a sibling TEXT block whose first
   // line is "Base directory for this skill: <dir>/<name>" — not the tool_result.
-  function requestWithSkillTextBlock(skillDirName: string, textLen: number, cc?: { blockedSkills?: string[] }) {
-    const bundle = `Base directory for this skill: /private/tmp/claude-501/bundled-skills/2.1.207/abc/${skillDirName}\n\n` + "DOCS ".repeat(Math.ceil(textLen / 5));
+  function requestWithSkillTextBlock(skillDirName: string, textLen: number, cc?: { blockedSkills?: string[] }, baseDir?: string) {
+    const dir = baseDir ?? `/private/tmp/claude-501/bundled-skills/2.1.207/abc/${skillDirName}`;
+    const bundle = `Base directory for this skill: ${dir}\n\n` + "DOCS ".repeat(Math.ceil(textLen / 5));
     return anthropicToResponsesTranslation({
       model: "gemini/gemini-3-pro",
       max_tokens: 100,
@@ -344,6 +345,27 @@ describe("bundled-skill elision for routed models (devlog 260712 060)", () => {
     const off = userTexts(requestWithSkillTextBlock("claude-api", 500_000, { blockedSkills: [] }));
     expect(off.some(t => t.length > 400_000)).toBe(true);
   });
+
+  test("text-block carrier: Windows backslash base dir is elided (live incident 2026-07-15)", () => {
+    const texts = userTexts(requestWithSkillTextBlock("claude-api", 500_000, undefined,
+      "C:\\Users\\user\\AppData\\Roaming\\npm\\node_modules\\bundled-skills\\claude-api"));
+    expect(texts.some(t => t.includes("elided") && t.includes("claude-api"))).toBe(true);
+    expect(texts.every(t => t.length < 10_000)).toBe(true);
+  });
+
+  test("text-block carrier: mixed separators and UNC paths are elided", () => {
+    const mixed = userTexts(requestWithSkillTextBlock("claude-api", 500_000, undefined,
+      "C:\\Users\\u\\skills/2.1.207\\claude-api"));
+    expect(mixed.some(t => t.includes("elided"))).toBe(true);
+    const unc = userTexts(requestWithSkillTextBlock("claude-api", 500_000, undefined,
+      "\\\\server\\share\\skills\\claude-api"));
+    expect(unc.some(t => t.includes("elided"))).toBe(true);
+  });
+
+  test("text-block carrier: drive-relative dir (no separator) stays pass-through", () => {
+    const texts = userTexts(requestWithSkillTextBlock("claude-api", 500_000, undefined, "C:claude-api"));
+    expect(texts.some(t => t.length > 400_000)).toBe(true);
+  });
 });
 
 describe("ocx-route directive (devlog 072)", () => {