feat(windows): add first-class pwsh/powershell support (#16069)

packages/opencode/src/tool/bash.txt

@@ -1,6 +1,8 @@
 Executes a given bash command in a persistent shell session with optional timeout, ensuring proper handling and security measures.
 
-All commands run in current working directory by default. Use the `workdir` parameter if you need to run a command in a different directory. AVOID using `cd <directory> && <command>` patterns - use `workdir` instead.
+Be aware: OS: ${os}, Shell: ${shell}
+
+All commands run in ${directory} by default. Use the `workdir` parameter if you need to run a command in a different directory. AVOID using `cd <directory> && <command>` patterns - use `workdir` instead.
 
 IMPORTANT: This tool is for terminal operations like git, npm, docker, etc. DO NOT use it for file operations (reading, writing, editing, searching, finding files) - use the specialized tools for this instead.
 
@@ -35,7 +37,7 @@ Usage notes:
     - Communication: Output text directly (NOT echo/printf)
   - When issuing multiple commands:
     - If the commands are independent and can run in parallel, make multiple Bash tool calls in a single message. For example, if you need to run "git status" and "git diff", send a single message with two Bash tool calls in parallel.
-    - If the commands depend on each other and must run sequentially, use a single Bash call with '&&' to chain them together (e.g., `git add . && git commit -m "message" && git push`). For instance, if one operation must complete before another starts (like mkdir before cp, Write before Bash for git operations, or git add before git commit), run these operations sequentially instead.
+    - ${chaining}
     - Use ';' only when you need to run commands sequentially but don't care if earlier commands fail
     - DO NOT use newlines to separate commands (newlines are ok in quoted strings)
   - AVOID using `cd <directory> && <command>`. Use the `workdir` parameter to change directories instead.