Version OpenCode skills and plugins

Repository sits at the OpenCode config root rather than inside skills/ or
plugins/. OpenCode scans exactly those two subdirectories, and a .git
directory inside either one is picked up as a plugin and fails to load:

  loading plugin id=.../plugins/.git entrypoint=.../plugins/.git/index
  failed to load plugin ... AggregateError: 2 errors building .../plugins/.git/index

The watcher.ignore config option does not help: it only suppresses filesystem
update events, not plugin discovery, and the "-" disable prefix only applies to
plugins listed in opencode.json(c), not auto-discovered ones.

.gitignore admits only skills/ and plugins/ (plus itself). Personal config
(opencode.jsonc, cli.json, service.json) and node_modules stay local.

skills/opencode-plugins  V2-only plugin authoring reference and 7 templates,
                         transcribed from the V2 docs with the URL on every file
plugins/searxng-search   searxng_search tool over a self-hosted SearXNG JSON API

skills/opencode-plugins/templates/rpc-implementation-effect.ts

@@ -0,0 +1,74 @@
+// RPC implementation (Effect flavor) — template
+//
+// Docs: https://opencode.ai/v2/docs/build/plugins/effect/rpc/
+//
+// Needs templates/rpc-effect.ts copied next to this file as src/rpc.ts, so the
+// doc's "./rpc.js" specifier resolves. Rename it rpc.ts on save; the contract
+// shape is identical, only the schema dialect differs.
+//
+// Registration goes inside the plugin `effect`, NOT `setup`.
+
+//
+// The docs use "@opencode/plugin" and "@opencode/plugin/effect". Install the
+// package at your OpenCode version and restart the service first — see the
+// PREREQUISITE block in promise-plugin.ts.
+import { Plugin } from "@opencode/plugin/effect"
+import { Effect, Stream } from "effect"
+import { Acme } from "./rpc.js"
+
+export default Plugin.define({
+  id: "acme-effect-plugin",
+
+  effect: (ctx) =>
+    Effect.gen(function* () {
+      const registration = yield* ctx.rpc.register(Acme, {
+        // Input arrives already decoded — destructure it, do not cast.
+        search: ({ query }, context) =>
+          findText(query).pipe(
+            Effect.flatMap((text) =>
+              text
+                ? Effect.succeed({ text })
+                : Effect.fail(context.error("not_found", "Result not found", { query })),
+            ),
+          ),
+      })
+
+      // The same plugin can call its own RPC.
+      const acme = ctx.rpc(Acme)
+      const result = yield* acme.search({ query: "hello" })
+
+      yield* registration.events.emit("updated", { itemID: "item-1", text: result.text })
+
+      // Subscriptions are a Stream; forkScoped handles interruption.
+      // "Subscriptions are live only and close when Stream consumption stops."
+      yield* acme.events.subscribe("updated").pipe(
+        Stream.runForEach((event) => Effect.logInfo(event.data.text)),
+        Effect.forkScoped,
+      )
+
+      // context.signal is NOT documented on the Effect page. Use interruption.
+    }).pipe(Effect.orDie),
+})
+
+// Calling over HTTP uses the Effect client and needs an HTTP client layer:
+//
+//   import { OpenCode } from "@opencode/client/effect"
+//   import { Effect } from "effect"
+//   import { FetchHttpClient } from "effect/unstable/http"
+//   import { Acme } from "opencode-acme-plugin/rpc"
+//
+//   const program = Effect.gen(function* () {
+//     const client = yield* OpenCode.make({ baseUrl: "http://localhost:4096" })
+//     const acme = client.rpc(Acme)
+//     return yield* acme.search({ query: "hello" })
+//   })
+//
+//   const result = await Effect.runPromise(
+//     program.pipe(Effect.provide(FetchHttpClient.layer)),
+//   )
+//
+// Another Effect plugin calls it with ctx.rpc(Acme). events.on and the
+// prefixed event type are documented only on the Promise page — check before
+// relying on either here.
+
+declare function findText(query: string): Effect.Effect<string | undefined>