feat(agent): search_documents tool — the model can grep the indexed documents for an exact string

tests/integration/test_api.py

@@ -298,17 +298,20 @@ def test_ui_chrome_has_no_emoji(client, path: str) -> None:
     the JS that renders it, and the stylesheet — is emoji-free.
 
     Phase 37 revision (owner permission 2026-08-26, PLAN §4): the agent's
-    ``.tool-call`` line carries two CONTENT marks — 🔎 (list) and 📄
+    ``.tool-call`` line carries the CONTENT marks — 🔎 (list) and 📄
     (read) — the only emoji in the whole frontend, and only as the exact
-    tool-line template strings in app.js. The guard strips precisely
-    those two literals; any other emoji, or those marks anywhere else,
-    still fails."""
+    tool-line template strings in app.js. Phase 68 revision: the
+    ``search_documents`` tool line adds the third template literal
+    ("🔎 Searching for "). The guard strips precisely those three
+    literals; any other emoji, or those marks anywhere else, still
+    fails."""
     r = client.get(path)
     assert r.status_code == 200
     text = r.text
     if path in ("/assets/app.js", "/assets/shared.js"):
         text = text.replace('"🔎 Listing documents"', "")
         text = text.replace('"📄 Reading "', "")
+        text = text.replace('"🔎 Searching for "', "")
     assert _find_emoji(text) == [], f"emoji found in {path}: {_find_emoji(text)!r}"