fix(pwsh): close the remaining review threads

- scrubbedParentEnv folds case before the DSH_ prefix check (Windows env
  names are case-insensitive; a parent dsh_* entry read back as \*
  in the child) and the service spec pins the lowercase probe.
- The acp.snapshot.ts pwsh probe follows resolvePwshPath() like the package
  suites, so a Windows host with only an install-location pwsh still runs
  the scenario.
- pwsh-tool-turn is re-recorded around [Console]::Out.Write('PWSH_OK'):
  the fixture carries no platform newline, so one recording replays on
  Windows and POSIX alike (record + refresh; replay-verified keyless).
- The pwsh-local Known Limitations bullet drops the self-defeating no-op
  advice: & { } is scoped to param(...), using/#requires scripts run from a
  file (both languages, pairing re-recorded).
- The capability-seams graph moves ctx.bashEnv ownership to bash-env and
  lists pwsh-local/tool-pwsh on the ctx.bash seam (source updated,
  docs regenerated).
- The tool-bash presenter fixture retires the stale 'command aborted'
  literal for the shipped 'tool call aborted' message.

packages/bash/tool-bash/tests/tools.spec.ts

@@ -1017,9 +1017,9 @@ describe('tool-owned UI presentation (presentCall / presentResult)', () => {
     // not renderResult output, so a generic fenced card, no terminal output/exit.
     const out = ctx.tools.get('bash')!.presentResult!(
       { command: 'x', description: 'x' },
-      { content: [{ type: 'text', text: 'command aborted' }], isError: true },
+      { content: [{ type: 'text', text: 'tool call aborted' }], isError: true },
     )
-    expect(out).toEqual({ card: 'generic', content: [{ type: 'text', text: '```console\ncommand aborted\n```' }] })
+    expect(out).toEqual({ card: 'generic', content: [{ type: 'text', text: '```console\ntool call aborted\n```' }] })
   })
 
   it('bash presentResult: leaves a non-text (unexpected) result untouched → undefined (UI keeps raw content)', async () => {