feat(agent): cross-char search_items tool + bump timeouts

Adds an MCP tool wrapping the inventory-service /search/items endpoint
with include_all_characters=true, so questions like 'find me a bracelet
with Legendary Acid Ward on any unequipped char' resolve in ONE tool call
instead of looping get_inventory over 60+ chars (which timed out at 120s).

- agent/tools.py: search_items_global wrapper
- agent/mcp_overlord.py: register new tool with detailed schema doc
- agent/claude_wrapper.py: include in --allowed-tools whitelist;
  bump timeout 120s -> 240s
- nginx/overlord.conf: bump /api/agent/ proxy timeout 180s -> 300s
- CLAUDE.md: brief Claude to USE search_items for cross-char searches

agent/tools.py

@@ -297,6 +297,40 @@ async def get_inventory_search(
     return resp.json()
 
 
+async def search_items_global(filters: dict[str, Any]) -> dict[str, Any]:
+    """Cross-character item search via the inventory service's /search/items.
+
+    Use this INSTEAD of looping per-character when the user asks "find an X
+    on any of my chars" — one DB query vs. 60+ HTTP roundtrips.
+
+    Common filter keys (passed straight through as query params):
+      include_all_characters: bool (set true to search every char)
+      character: str (single char) | characters: "A,B,C"
+      text: str (name/description substring)
+      has_spell: "Legendary Acid Ward"      — exact spell name
+      spell_contains: "Legendary"           — substring match
+      legendary_cantrips: "Foo,Bar"
+      equipment_status: "equipped" | "unequipped"
+      equipment_slot: int (bitmask: 4=chest, 2048=bracelet, 4096=ring, ...)
+      slot_names: "Bracelet,Ring"
+      armor_only / jewelry_only / weapon_only: bool
+      min_armor / max_armor / min_damage / max_damage: int
+      ...and many more — see /search/items endpoint docs.
+    """
+    client = await _http()
+    # Default to all-character search if caller didn't scope; otherwise the
+    # endpoint refuses with a 400.
+    params = dict(filters or {})
+    if not any(
+        k in params
+        for k in ("character", "characters", "include_all_characters")
+    ):
+        params["include_all_characters"] = True
+    resp = await client.get("/search/items", params=params)
+    resp.raise_for_status()
+    return resp.json()
+
+
 async def get_combat_stats(character_name: str) -> dict[str, Any]:
     """Lifetime + session combat stats for one character (per-element split,
     monster encounters, surge counts)."""