fix: 修正 logo 中 N 和 G 字母造型

N 添加对角线笔画（█▄ █），G 添加内横杠（█ ▀█），
避免与 O 字母造型雷同。同步更新 ui.ts 中的硬编码 wordmark。

packages/opencode/test/cli/help/help-snapshots.test.ts

@@ -0,0 +1,137 @@
+// Help-text snapshots for every CLI command + key subcommand. Catches
+// accidental flag removals, renames, and reordering in a single sweep —
+// any change to the user-visible CLI surface shows up here as a diff.
+//
+// This is the broad coverage layer that makes the future Effect CLI
+// migration (yargs → effect-smol/cli) safe to attempt: if a refactor
+// preserves the surface, the snapshots stay green; if it doesn't, the
+// diff tells you exactly which command(s) changed.
+//
+// Snapshots are taken at COLUMNS=120 so wrapping is stable across
+// terminal sizes. The default opencode tui command is excluded —
+// `opencode --help` includes an ASCII banner that pulls in the install
+// version (changes per release), so we'd snapshot a moving target.
+import { describe, expect } from "bun:test"
+import { Effect } from "effect"
+import { EOL } from "os"
+import { cliIt } from "../../lib/cli-process"
+import { normalizeForSnapshot, PATH_SEP } from "../../lib/snapshot"
+
+// Composes `normalizeForSnapshot` (CRLF + tmpdir) with two help-specific
+// rules:
+//
+//   1. The harness's `oc-cli-XXX` subdir under TMPDIR collapses to `<HOME>`.
+//      `PATH_SEP` matches `/` and `\\` so the rule works on POSIX + Windows.
+//
+//   2. yargs wraps the `[string] [default: "..."]` clause based on the
+//      pre-normalized default's character length, so different random home
+//      path widths produce different leading-whitespace counts (or even
+//      line-wraps onto a fresh line on Windows). `\s+` matches both forms.
+function normalize(text: string): string {
+  return normalizeForSnapshot(text, {
+    pathReplacements: [
+      // Mixed-case [A-Za-z0-9] because node's mkdtemp suffix is mixed-case
+      // (the harness now uses FileSystem.makeTempDirectoryScoped under the
+      // hood). A `[a-z0-9]+` regex would leave uppercase chars trailing.
+      [new RegExp(`<TMPDIR>${PATH_SEP}oc-cli-[A-Za-z0-9]+`, "g"), "<HOME>"],
+      [/\s+\[string\] \[default: "<HOME>"\]/g, ' [string] [default: "<HOME>"]'],
+    ],
+  })
+}
+
+// Top-level commands. Order matches what `opencode --help` prints today;
+// keep it in that order so the snapshot file reads as a table of contents.
+// `completion` is intentionally excluded — it's a yargs built-in that emits
+// top-level help on `--help` and exits 1; not a real opencode command.
+const TOP_LEVEL = [
+  "acp",
+  "mcp",
+  "attach",
+  "run",
+  "debug",
+  "providers", // aliased to `auth`
+  "agent",
+  "upgrade",
+  "uninstall",
+  "serve",
+  "web",
+  "models",
+  "stats",
+  "export",
+  "import",
+  "github",
+  "pr",
+  "session",
+  "plugin",
+  "db",
+] as const
+
+// Subcommands worth pinning. Not exhaustive — the goal is one snapshot per
+// distinct argv shape, not every leaf. Add new entries when a subcommand
+// gains user-visible flags that we want to lock in.
+const SUBCOMMANDS = [
+  ["mcp", "list"],
+  ["mcp", "add"],
+  ["mcp", "auth"],
+  ["mcp", "logout"],
+  ["providers", "list"],
+  ["providers", "login"],
+  ["providers", "logout"],
+  ["agent", "create"],
+  ["agent", "list"],
+  ["session", "list"],
+  ["session", "delete"],
+  ["github", "install"],
+  ["github", "run"],
+  ["db", "path"],
+] as const
+
+// Fixed wrap width so a developer's terminal doesn't affect snapshots.
+// yargs honors COLUMNS; CI runners typically default to 80 which produces
+// different wraps from a 200-col local terminal.
+const SNAPSHOT_ENV = { COLUMNS: "120" }
+
+describe("opencode CLI help-text snapshots", () => {
+  // Single test, parallel spawns. Each command's help fires under
+  // `concurrency: 8` — wall-clock stays under ~10s even for ~35 commands,
+  // versus ~1 minute if we serialized.
+  cliIt.live(
+    "every documented command emits stable help text",
+    ({ opencode }) =>
+      Effect.gen(function* () {
+        const topLevel = yield* opencode.spawn(["--help"], { env: SNAPSHOT_ENV })
+        expect(topLevel.exitCode).toBe(0)
+        expect(topLevel.stderr.endsWith(EOL)).toBe(true)
+
+        const argvs: Array<readonly string[]> = [...TOP_LEVEL.map((c) => [c] as const), ...SUBCOMMANDS]
+
+        // Spawn in parallel, then assert in argv order so snapshot output is
+        // deterministic and per-command failures don't abort the rest of
+        // the sweep. `Effect.partition` is the canonical "run all, separate
+        // failures from successes" primitive — no mutable accumulator needed.
+        const [failures, results] = yield* Effect.partition(
+          argvs,
+          (argv) =>
+            Effect.gen(function* () {
+              const result = yield* opencode.spawn([...argv, "--help"], { env: SNAPSHOT_ENV })
+              if (result.exitCode !== 0) {
+                return yield* Effect.fail(`opencode ${argv.join(" ")}: exit ${result.exitCode}`)
+              }
+              return { argv, result }
+            }),
+          { concurrency: 8 },
+        )
+
+        for (const { argv, result } of results) {
+          // yargs writes --help to stderr, not stdout. Snapshotting stderr
+          // means our test catches the help body; stdout for these commands
+          // is expected to be empty.
+          expect(normalize(result.stderr)).toMatchSnapshot(`opencode ${argv.join(" ")} --help`)
+        }
+        if (failures.length > 0) {
+          throw new Error(`Help text failed for:\n  ${failures.join("\n  ")}`)
+        }
+      }),
+    180_000,
+  )
+})