fix: sidebar shows OpenCode instead of Altimate Code after upstream merge

- Replace `<b>Open</b><b>Code</b>` with `<b>Altimate</b><b> Code</b>` in sidebar footer
- Add `altimate_change` markers to protect branding block from future upstream merges
- Add TUI branding guard tests to `upstream-merge-guard.test.ts`

Closes #167

Author: anandgupta42

packages/opencode/src/cli/cmd/tui/routes/session/sidebar.tsx

@@ -307,13 +307,15 @@ export function Sidebar(props: { sessionID: string; overlay?: boolean }) {
             <span style={{ fg: theme.textMuted }}>{directory().split("/").slice(0, -1).join("/")}/</span>
             <span style={{ fg: theme.text }}>{directory().split("/").at(-1)}</span>
           </text>
+          {/* altimate_change start — sidebar branding */}
           <text fg={theme.textMuted}>
-            <span style={{ fg: theme.success }}>•</span> <b>Open</b>
+            <span style={{ fg: theme.success }}>•</span> <b>Altimate</b>
             <span style={{ fg: theme.text }}>
-              <b>Code</b>
+              <b> Code</b>
             </span>{" "}
             <span>{Installation.VERSION}</span>
           </text>
+          {/* altimate_change end */}
         </box>
       </box>
     </Show>

packages/opencode/test/branding/upstream-merge-guard.test.ts

@@ -38,11 +38,11 @@ describe("Installation script branding", () => {
     // Should not contain the upstream npm package name in install commands
     // (note: @opencode-ai/ as internal scope is allowed, but `opencode-ai@` as
     // an npm install target is not)
-    const installLines = installSrc.split("\n").filter(
-      (line) =>
-        (line.includes("npm") || line.includes("pnpm") || line.includes("bun")) &&
-        line.includes("install"),
-    )
+    const installLines = installSrc
+      .split("\n")
+      .filter(
+        (line) => (line.includes("npm") || line.includes("pnpm") || line.includes("bun")) && line.includes("install"),
+      )
     for (const line of installLines) {
       expect(line).not.toMatch(/["'`]opencode-ai["'`@]/)
     }
@@ -206,13 +206,13 @@ describe("OAuth/MCP branding", () => {
   const oauthProviderPath = join(srcDir, "mcp", "oauth-provider.ts")
   const oauthCallbackPath = join(srcDir, "mcp", "oauth-callback.ts")
 
-  test("oauth-provider.ts has client_name: \"Altimate Code\" not \"OpenCode\"", () => {
+  test('oauth-provider.ts has client_name: "Altimate Code" not "OpenCode"', () => {
     const content = readText(oauthProviderPath)
     expect(content).toContain('client_name: "Altimate Code"')
     expect(content).not.toMatch(/client_name:\s*"OpenCode"/)
   })
 
-  test("oauth-callback.ts HTML titles contain \"Altimate Code\" not \"OpenCode\"", () => {
+  test('oauth-callback.ts HTML titles contain "Altimate Code" not "OpenCode"', () => {
     const content = readText(oauthCallbackPath)
     // All <title> tags should reference Altimate Code
     const titleMatches = content.match(/<title>[^<]+<\/title>/g) ?? []
@@ -300,6 +300,25 @@ describe("No opencode.ai domain leaks in src/", () => {
   })
 })
 
+// ---------------------------------------------------------------------------
+// 5b. TUI Branding (sidebar, headers, etc.)
+// ---------------------------------------------------------------------------
+describe("TUI branding", () => {
+  const sidebarPath = join(srcDir, "cli", "cmd", "tui", "routes", "session", "sidebar.tsx")
+  const sidebarContent = readText(sidebarPath)
+
+  test("sidebar shows 'Altimate' not 'Open' as branded name", () => {
+    // The sidebar footer must say "Altimate Code", not "OpenCode"
+    expect(sidebarContent).toContain("<b>Altimate</b>")
+    expect(sidebarContent).not.toMatch(/<b>Open<\/b>\s*\n\s*<span[^>]*>\s*<b>Code<\/b>/)
+  })
+
+  test("sidebar has altimate_change marker to protect branding", () => {
+    expect(sidebarContent).toContain("altimate_change start")
+    expect(sidebarContent).toContain("altimate_change end")
+  })
+})
+
 // ---------------------------------------------------------------------------
 // 6. Build & Package Branding
 // ---------------------------------------------------------------------------