feat(core): add pluggable web search (#35558)

Co-authored-by: Dax Raad <d@ironbay.co>

packages/core/src/config/plugin/websearch.ts

@@ -0,0 +1,27 @@
+export * as ConfigWebSearchPlugin from "./websearch"
+
+import { define } from "@opencode-ai/plugin/v2/effect/plugin"
+import { Effect, Stream } from "effect"
+import { Config } from "../../config"
+
+export const Plugin = define({
+  id: "opencode.config.websearch",
+  effect: Effect.fn(function* (ctx) {
+    const config = yield* Config.Service
+    const loaded = { entries: yield* config.entries() }
+    yield* ctx.websearch.transform((websearch) => {
+      const providerID = Config.latest(loaded.entries, "websearch")?.provider
+      if (providerID) websearch.default.set(providerID)
+    })
+    yield* ctx.event.subscribe().pipe(
+      Stream.filter((event) => event.type === "config.updated"),
+      Stream.runForEach(() =>
+        config.entries().pipe(
+          Effect.tap((entries) => Effect.sync(() => (loaded.entries = entries))),
+          Effect.andThen(ctx.websearch.reload()),
+        ),
+      ),
+      Effect.forkScoped({ startImmediately: true }),
+    )
+  }),
+})

packages/core/src/config/websearch.ts

@@ -0,0 +1,8 @@
+export * as ConfigWebSearch from "./websearch"
+
+import { WebSearch } from "@opencode-ai/schema/websearch"
+import { Schema } from "effect"
+
+export class Info extends Schema.Class<Info>("ConfigWebSearch.Info")({
+  provider: WebSearch.ID,
+}) {}