test(bash): fix env parameter tests for Windows compatibility

Use Bun's process.env instead of shell-specific echo syntax for cross-platform support

- Replace Unix $VAR syntax with bun -e "console.log(process.env.VAR)"

- Use existing test helpers (bin, evalarg) for proper quoting

- Tests now pass on Windows regardless of shell type

Author: taxilian

packages/opencode/test/tool/bash.test.ts

@@ -1099,14 +1099,15 @@ describe("tool.bash truncation", () => {
 })
 
 describe("tool.bash env", () => {
-  test("sets environment variables", async () => {
+  each("sets environment variables", async () => {
     await Instance.provide({
       directory: projectRoot,
       fn: async () => {
         const bash = await BashTool.init()
+        const code = "console.log(process.env.TEST_VAR)"
         const result = await bash.execute(
           {
-            command: "echo $TEST_VAR",
+            command: `${bin} -e ${evalarg(code)}`,
             description: "Echo environment variable",
             env: { TEST_VAR: "hello_world" },
           },
@@ -1118,21 +1119,23 @@ describe("tool.bash env", () => {
     })
   })
 
-  test("sets multiple environment variables", async () => {
+  each("sets multiple environment variables", async () => {
     await Instance.provide({
       directory: projectRoot,
       fn: async () => {
         const bash = await BashTool.init()
+        const code = "console.log(process.env.VAR1, process.env.VAR2)"
         const result = await bash.execute(
           {
-            command: "echo $VAR1 $VAR2",
+            command: `${bin} -e ${evalarg(code)}`,
             description: "Echo multiple environment variables",
             env: { VAR1: "foo", VAR2: "bar" },
           },
           ctx,
         )
         expect(result.metadata.exit).toBe(0)
-        expect(result.output).toContain("foo bar")
+        expect(result.output).toContain("foo")
+        expect(result.output).toContain("bar")
       },
     })
   })