fix: remove Current date from env context since OpenCode already provides it

date is already injected by OpenCode's system.ts. omo-env now contains only
Timezone and Locale, which are stable across requests and never break cache.

src/agents/env-context.test.ts

@@ -4,7 +4,7 @@ import { describe, test, expect } from "bun:test"
 import { createEnvContext } from "./env-context"
 
 describe("createEnvContext", () => {
-  test("returns omo-env block with date, timezone, and locale", () => {
+  test("returns omo-env block with timezone and locale", () => {
     // #given - no setup needed
 
     // #when
@@ -13,9 +13,9 @@ describe("createEnvContext", () => {
     // #then
     expect(result).toContain("<omo-env>")
     expect(result).toContain("</omo-env>")
-    expect(result).toContain("Current date:")
     expect(result).toContain("Timezone:")
     expect(result).toContain("Locale:")
+    expect(result).not.toContain("Current date:")
   })
 
   test("does not include time with seconds precision to preserve token cache", () => {
@@ -28,13 +28,14 @@ describe("createEnvContext", () => {
     expect(result).not.toMatch(/\d{1,2}:\d{2}:\d{2}/)
   })
 
-  test("does not include Current time field", () => {
-    // #given - time field (even without seconds) changes every minute, degrading cache
+  test("does not include date or time fields since OpenCode already provides them", () => {
+    // #given - OpenCode's system.ts already injects date, platform, working directory
 
     // #when
     const result = createEnvContext()
 
-    // #then - time field entirely removed; date-level precision is sufficient
+    // #then - only timezone and locale remain; both are stable across requests
+    expect(result).not.toContain("Current date:")
     expect(result).not.toContain("Current time:")
   })
 })

src/agents/env-context.ts

@@ -5,20 +5,11 @@
  * See: https://github.com/code-yeongyu/oh-my-opencode/issues/379
  */
 export function createEnvContext(): string {
-  const now = new Date()
   const timezone = Intl.DateTimeFormat().resolvedOptions().timeZone
   const locale = Intl.DateTimeFormat().resolvedOptions().locale
 
-  const dateStr = now.toLocaleDateString(locale, {
-    weekday: "short",
-    year: "numeric",
-    month: "short",
-    day: "numeric",
-  })
-
   return `
 <omo-env>
-  Current date: ${dateStr}
   Timezone: ${timezone}
   Locale: ${locale}
 </omo-env>`