feat(bash): add config option to hide env prefix in command display

[magnusrodseth]

Summary

Add a config option to hide Claude's environment variable prefix in bash command display while keeping it intact for execution.

When using OpenCode with Claude (Anthropic) as the model provider, Claude adds a safety env prefix to bash commands:

export CI=true DEBIAN_FRONTEND=noninteractive GIT_TERMINAL_PROMPT=0 GCM_INTERACTIVE=never HOMEBREW_NO_AUTO_UPDATE=1 GIT_EDITOR=: EDITOR=: VISUAL='' GIT_SEQUENCE_EDITOR=: GIT_MERGE_AUTOEDIT=no GIT_PAGER=cat PAGER=cat npm_config_yes=true PIP_NO_INPUT=1 YARN_ENABLE_IMMUTABLE_INSTALLS=false; git status

This creates visual noise in the TUI. This PR adds a config option to hide this prefix in the display only - the command still executes with the env vars.

Changes

• packages/util/src/bash.ts - New stripEnvPrefix() utility function
• packages/opencode/src/config/config.ts - Add Bash config schema with hideEnvPrefix option
• packages/opencode/src/cli/cmd/tui/routes/session/index.tsx - Apply filter in TUI Bash component
• packages/opencode/test/util/bash.test.ts - Unit tests for the utility function

Usage

Add to opencode.json:

{
  "bash": {
    "hideEnvPrefix": true
  }
}

Before/After

Before (default, hideEnvPrefix: false):

$ export CI=true DEBIAN_FRONTEND=noninteractive ...; git status

After (hideEnvPrefix: true):

$ git status

Notes

• Default is false for backwards compatibility
• Web share view is unchanged (shows actual executed command, no config access)
• Display-only change - execution is unchanged

Closes #8668 Related to #2581