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-effect.ts

@@ -0,0 +1,55 @@
+// RPC contract (Effect flavor) — template
+//
+// Docs: https://opencode.ai/v2/docs/build/plugins/effect/rpc/
+//
+// Copy to src/rpc.ts — the implementation template's doc-accurate import is
+// "./rpc.js", so the file must be named rpc.ts. Contract only, no
+// implementation. Same contract shape as rpc.ts, but with Effect Schema
+// instead of raw JSON Schema. Registered by rpc-implementation-effect.ts.
+//
+// Rpc.define is imported from "@opencode/plugin/rpc" here too, NOT from
+// "@opencode/plugin/effect". The Effect page imports Schema from the root
+// "effect" module.
+//
+// TYPE NOTE: the shipped `ValueSchema` type is
+//   Schema.Codec | StandardSchemaV1 | JsonSchema
+// and Effect's `Schema.Struct` is not a `Codec`, so `tsc --strict` can reject
+// the form below. The page states JSON Schema and Standard Schema are supported
+// here too, so either of these typechecks instead:
+//   input: { type: "object", properties: { query: { type: "string" } }, required: ["query"] }
+//   input: z.object({ query: z.string() })     // or Valibot / ArkType
+// A method needs BOTH input and output to be present for the types to line up.
+
+//
+// PREREQUISITE: install @opencode/plugin at your OpenCode version and restart
+// the service — see the PREREQUISITE block in promise-plugin.ts.
+//
+import { Rpc } from "@opencode/plugin/rpc"
+import { Schema } from "effect"
+
+export const Acme = Rpc.define({
+  // The page does not describe how `id` affects method routing. Pick a name
+  // that will not collide.
+  id: "acme",
+  methods: {
+    search: {
+      // Effect Schema validates and infers types, so the handler needs no casts.
+      input: Schema.Struct({ query: Schema.String }),
+      output: Schema.Struct({ text: Schema.String }),
+      // Omit input or output if the method takes or returns nothing.
+      // Each error key becomes the error's `type`.
+      errors: {
+        not_found: Schema.Struct({ query: Schema.String }),
+      },
+    },
+  },
+  events: {
+    // Event data must be an object.
+    updated: {
+      schema: Schema.Struct({ itemID: Schema.String, text: Schema.String }),
+    },
+  },
+})
+
+// The Effect page also states that JSON Schema and Standard Schema are
+// supported here, so an Effect contract is not restricted to Effect Schema.