feat: build out discord support agent (#4)

### Explanation

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### Issue

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### Attestations

- [x] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [x] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [x] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [x] I have pinned the dependencies to a specific patch version.

### Style

- [x] I have run the linter and resolved any errors.
- [x] My pull request uses an appropriate title, matching the conventional commit standards.
- [x] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

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Reviewed-on: #4
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

bot/prod/modules/ai.js

@@ -0,0 +1,89 @@
+/**
+ * @copyright nhcarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+/* eslint-disable no-await-in-loop -- Ordinarily I would use Promise.all, but we want these sent in order. */
+// eslint-disable-next-line @typescript-eslint/naming-convention -- It is a class, so should be uppercased.
+import Anthropic from "@anthropic-ai/sdk";
+import { prompt } from "../config/prompt.js";
+import { calculateCost } from "../utils/calculateCost.js";
+import { errorHandler } from "../utils/errorHandler.js";
+const anthropic = new Anthropic({
+    apiKey: process.env.ANTHROPIC_KEY ?? "",
+    timeout: 5 * 60 * 1000,
+});
+/**
+ * Formats Discord messages into a prompt for the AI,
+ * sends the prompt to the AI, and returns the AI's response.
+ * @param hikari - Hikari's Discord instance.
+ * @param messages - The Discord messages to process.
+ * @param username - The username of the user who triggered this request - that is, the author of the most recent message.
+ * @param channel - The channel in which to respond.
+ * @returns The AI's response as a string.
+ */
+// eslint-disable-next-line max-lines-per-function -- This is a big function, but it does a lot of things.
+export const ai = async (hikari, messages, username, channel) => {
+    try {
+        const typingInterval = setInterval(() => {
+            void channel.sendTyping();
+        }, 3000);
+        const parsedPrompt = prompt.replace("{{username}}", username);
+        const result = await anthropic.beta.messages.create({
+            betas: ["web-search-2025-03-05"],
+            // eslint-disable-next-line @typescript-eslint/naming-convention -- API requirement
+            max_tokens: 20_000,
+            messages: messages.map((message) => {
+                return {
+                    content: message.content,
+                    role: message.author.id === hikari.user?.id
+                        ? "assistant"
+                        : "user",
+                };
+            }),
+            model: "claude-sonnet-4-20250514",
+            system: parsedPrompt,
+            temperature: 1,
+            tools: [
+                {
+                    // eslint-disable-next-line @typescript-eslint/naming-convention -- API requirement
+                    allowed_domains: ["nhcarrigan.com"],
+                    name: "web_search",
+                    type: "web_search_20250305",
+                },
+            ],
+        });
+        await calculateCost(result.usage, username);
+        for (const payload of result.content) {
+            await channel.sendTyping();
+            // Sleep for 5 seconds,
+            await new Promise((resolve) => {
+                // eslint-disable-next-line no-promise-executor-return -- We want to wait for a bit.
+                return setTimeout(resolve, 3000);
+            });
+            if (payload.type === "text") {
+                await channel.send({ content: payload.text });
+            }
+            if (payload.type === "tool_use") {
+                await channel.send({ content: `Searching web via: ${String(payload.name)}` });
+            }
+            if (payload.type === "web_search_tool_result") {
+                if (Array.isArray(payload.content)) {
+                    await channel.send({
+                        content: `Checking content on:\n${payload.content.map((item) => {
+                            return `- [${item.title}](<${item.url}>)`;
+                        }).join("\n\n")}`,
+                    });
+                }
+                else {
+                    await channel.send({ content: `Web search error: ${payload.content.error_code}` });
+                }
+            }
+        }
+        clearInterval(typingInterval);
+    }
+    catch (error) {
+        const id = await errorHandler(error, "AI module");
+        await channel.send(`Something went wrong while processing your request. Please try again later, or [reach out in our support channel](<https://discord.com/channels/1354624415861833870/1385797209706201198>).\n-# ${id}`);
+    }
+};