feat: paste overflow via FlaskPaste for long replies

Add Bot.long_reply() that sends lines directly when under threshold,
or creates a FlaskPaste paste with preview + link when over. Refactor
abuseipdb, alert history, crtsh, dork, exploitdb, and subdomain
plugins to use long_reply(). Configurable paste_threshold (default: 4).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/derp/bot.py

@@ -460,6 +460,52 @@ class Bot:
         if target:
             await self.send(target, text)
 
+    async def long_reply(
+        self, msg: Message, lines: list[str], *,
+        label: str = "",
+    ) -> None:
+        """Reply with a list of lines; paste overflow to FlaskPaste.
+
+        If len(lines) <= paste_threshold, sends each line via send().
+        If len(lines) > paste_threshold, creates a paste with all lines
+        and sends a preview (first 2 lines) + paste URL.
+        Falls back to sending all lines if FlaskPaste is unavailable.
+        """
+        threshold = self.config["bot"].get("paste_threshold", 4)
+        target = msg.target if msg.is_channel else msg.nick
+
+        if not lines or not target:
+            return
+
+        if len(lines) <= threshold:
+            for line in lines:
+                await self.send(target, line)
+            return
+
+        # Attempt paste overflow
+        fp = self.registry._modules.get("flaskpaste")
+        paste_url = None
+        if fp:
+            full_text = "\n".join(lines)
+            loop = asyncio.get_running_loop()
+            paste_url = await loop.run_in_executor(
+                None, fp.create_paste, self, full_text,
+            )
+
+        if paste_url:
+            preview_count = min(2, threshold - 1)
+            for line in lines[:preview_count]:
+                await self.send(target, line)
+            remaining = len(lines) - preview_count
+            suffix = f" ({label})" if label else ""
+            await self.send(
+                target,
+                f"... {remaining} more lines{suffix}: {paste_url}",
+            )
+        else:
+            for line in lines:
+                await self.send(target, line)
+
     async def action(self, target: str, text: str) -> None:
         """Send a CTCP ACTION (/me) to a target."""
         await self.send(target, f"\x01ACTION {text}\x01")

src/derp/config.py

@@ -27,6 +27,7 @@ DEFAULTS: dict = {
         "plugins_dir": "plugins",
         "rate_limit": 2.0,
         "rate_burst": 5,
+        "paste_threshold": 4,
         "admins": [],
     },
     "channels": {},