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-quota.test.js

@@ -1,7 +1,7 @@
 /**
  * @file server-s3-quota.test.js
  * @description S3 plan, P4: plan quota per member home. `quotas({home})`
- * reads Claude, Codex, Cursor, Grok, Kimi Code and OpenCode Go from that
+ * reads Claude, Codex, Cursor and Kimi Code from that
  * Linux account's home only — never the host's logins, never agy — and only
  * files the member owns (review fix F3: a FIFO or another account's file is
  * not read). `GET /api/pricing/quota` gives a developer or an analyst their
@@ -32,16 +32,13 @@ process.env.CLAUDE_HOME = path.join(HOST, ".claude");
 process.env.CODEX_HOME = path.join(HOST, ".codex");
 process.env.XDG_CONFIG_HOME = path.join(HOST, ".config");
 process.env.AGENTHUB_CURSOR_DIR = path.join(HOST, ".cursor");
-process.env.GROK_HOME = path.join(HOST, ".grok");
 process.env.KIMI_CODE_HOME = path.join(HOST, ".kimi-code");
-process.env.XDG_DATA_HOME = path.join(HOST, ".local", "share");
 
 const { createApp, startServer } = require("../index");
 const auth = require("../lib/auth");
 const linux = require("../lib/linux-accounts");
 const runAs = require("../lib/run-as");
 const { quotas, __resetCache } = require("../lib/quota");
-const { Database } = require("../db");
 
 const LATER = Date.now() + 3600_000;
 const write = (file, body) => {
@@ -76,28 +73,12 @@ function seedHome(home, who, { codexPercent }) {
   write(path.join(home, ".cursor", "cli-config.json"), {
     authInfo: { email: `${who}@cursor`, userId: "u1" },
   });
-  write(path.join(home, ".grok", "auth.json"), {
-    "https://auth.x.ai": { key: `${who}-grok`, expires_at: new Date(LATER).toISOString() },
-  });
   write(path.join(home, ".kimi-code", "credentials", "kimi-code.json"), {
     access_token: `${who}-kimi`,
     expires_at: Math.floor(LATER / 1000),
   });
 }
 
-/** OpenCode 2 keeps its key in `opencode.db` (WAL), not `auth.json`. */
-function seedOpenCodeDb(home, key) {
-  const dir = path.join(home, ".local", "share", "opencode");
-  fs.mkdirSync(dir, { recursive: true });
-  const db = new Database(path.join(dir, "opencode.db"));
-  db.pragma?.("journal_mode = WAL");
-  db.exec(
-    "CREATE TABLE credential (integration_id TEXT, value TEXT, active INT, time_created INT)"
-  );
-  db.prepare("INSERT INTO credential VALUES ('opencode-go', ?, 1, 1)").run(JSON.stringify({ key }));
-  db.close();
-}
-
 let asked = [];
 const realFetch = global.fetch;
 global.fetch = async (url, opts = {}) => {
@@ -125,11 +106,7 @@ const setUid = (uid) => {
 
 before(async () => {
   seedHome(HOST, "host", { codexPercent: 77 });
-  write(path.join(HOST, ".local", "share", "opencode", "auth.json"), {
-    "opencode-go": { type: "api", key: "host-opencode" },
-  });
   seedHome(MIA, "mia", { codexPercent: 21 });
-  seedOpenCodeDb(MIA, "mia-opencode");
   setUid(process.getuid());
   fs.writeFileSync(
     process.env.AGENTHUB_SERVER_CONF,
@@ -159,27 +136,16 @@ describe("quotas({home}) reads a member's own logins", () => {
     __resetCache();
     asked = [];
     const { tools } = await quotas({ home: MIA });
-    assert.deepEqual(tools.map((t) => t.id).sort(), [
-      "claude",
-      "codex",
-      "cursor",
-      "grok",
-      "kimi",
-      "opencode",
-    ]);
+    assert.deepEqual(tools.map((t) => t.id).sort(), ["claude", "codex", "cursor", "kimi"]);
     const codex = tools.find((t) => t.id === "codex");
     assert.equal(codex.account, "mia@codex");
     assert.equal(codex.windows[0].usedPercent, 21);
     assert.equal(tools.find((t) => t.id === "cursor").account, "mia@cursor");
-    assert.ok(asked.length >= 6, asked.join(","));
+    assert.ok(asked.length >= 4, asked.join(","));
     assert.ok(
       asked.every((a) => a.includes("mia-")),
       `only mia's tokens leave: ${asked.join(",")}`
     );
-    assert.ok(
-      asked.some((a) => a.includes("mia-opencode")),
-      "OpenCode 2's db is read"
-    );
     assert.ok(tools.every((t) => t.label === undefined || t.label === null));
   });
 
@@ -195,8 +161,10 @@ describe("quotas({home}) reads a member's own logins", () => {
   });
 
   it("reads no file the member does not own, and never blocks on a FIFO", async () => {
-    fs.mkdirSync(path.join(BOB, ".grok"), { recursive: true });
-    require("node:child_process").execFileSync("mkfifo", [path.join(BOB, ".grok", "auth.json")]);
+    fs.mkdirSync(path.join(BOB, ".kimi-code", "credentials"), { recursive: true });
+    require("node:child_process").execFileSync("mkfifo", [
+      path.join(BOB, ".kimi-code", "credentials", "kimi-code.json"),
+    ]);
     __resetCache();
     assert.deepEqual((await quotas({ home: BOB })).tools, []);
     // mia's files now belong to another uid: none is read.