feat(ai-tools): drop OpenCode and Grok Build

- opencode.json / grok.json leave the built-in catalog; opencode-usage.js,
  its poller, transcript branch and table creation go with it (existing
  tables and session rows stay as history).
- A Grok payload reaching the Claude hook route (Grok runs the Claude hooks
  itself) is dropped instead of recorded as tool = 'grok'.
- quota.js no longer reads Grok or OpenCode Go logins.
- Redone on v2.8.22 from c6b2892 (feat/grok-usage, never merged).

server/__tests__/server-s3-tools.test.js

@@ -37,11 +37,11 @@ describe("what a publish copies", () => {
 
   it("a file in an npm package: the package folder (scoped too)", () => {
     const plain = write(
-      path.join(TMP, "npm", "lib", "node_modules", "opencode-ai", "bin", "oc.js"),
+      path.join(TMP, "npm", "lib", "node_modules", "some-cli", "bin", "oc.js"),
       "#!/usr/bin/env node\n"
     );
     assert.deepEqual(shared.planFor(plain), {
-      src: path.join(TMP, "npm", "lib", "node_modules", "opencode-ai"),
+      src: path.join(TMP, "npm", "lib", "node_modules", "some-cli"),
       entry: path.join("bin", "oc.js"),
     });
     const scoped = write(