feat(acp): render bash as a terminal card via the _meta convention

When the client advertises clientCapabilities._meta.terminal_output (Zed), a
bash tool call now renders as a real TERMINAL card — a cwd header + the command
+ its output — instead of the plain ```console text block. Keeps agent-side
dsh-bash execution; rejects the spec's client-side terminal/create (which would
bypass sandbox/env-scrub/ownership/cwd). Matches what claude-agent-acp and
codex-acp do; wire contract verified against Zed's source.

- dsh-tools: a provider-neutral ToolTerminal shape ({ cwd?, output? }) on
  ToolCallPresentation/ToolResultPresentation — a tool asks "render me as a
  terminal"; no ACP types leak in.
- dsh-tool-bash: bash presentCall marks terminal (cwd from an explicit absolute
  workdir, else left for the bridge to fill from the session cwd); presentResult
  carries the output alongside the ```console fallback.
- dsh-acp: initialize reads/remembers the _meta.terminal_output capability;
  streamSessionEventUpdate maps a terminal presentation to
  content:[{type:'terminal',terminalId}] + _meta.terminal_info on the call and
  _meta.terminal_output on the update WHEN capable — else the unchanged text
  path. terminalId is the callId; cwd defaults to the session header. The pure
  translator gained a TerminalRendering {enabled,cwd} param (off by default).

Tests via the REAL tool-bash + bash-local: capability ON -> terminal content +
_meta; OFF -> no _meta (text path). The with-key e2e adds a real-model terminal
card case (echo over ACP with the capability on). 773 tests, 100% coverage.

The exit-status pill (_meta.terminal_exit), live streaming
(_meta.terminal_output_delta), and command classification are RFC follow-ups.

packages/tool-bash/README.md

@@ -34,7 +34,7 @@ The owning agent is recorded per task id at spawn and kept for the lifetime of t
 
 ## UI presentation
 
-These tools own how their calls render in a UI (an editor's tool-call card) via the `dsh-tools` `presentCall`/`presentResult` seam — a UI never special-cases tool names. For `bash`: the **title** is the model-written `description` followed by the exact `command` ("List files in src — ls -la src"), `kind` is `execute` (terminal/run treatment), and the `command` is ALSO the **rawInput**. Why both in the title: an execute-kind card hides `rawInput` (Zed renders it only for non-terminal tools), so the command must ride in the always-visible title to be seen — the reference ACP adapters (claude-agent-acp, codex-acp) likewise put the command in an execute tool's title. The completed output is wrapped in a fenced ` ```console ` block — a UI-only affordance, so the model-facing result text stays unfenced. `bash_output`/`bash_kill` present a task-scoped title ("Read output from background task bash-3" / "Kill background task bash-3") with the task id as rawInput. These methods are pure/display-only (they also run on `session/load` replay), and a malformed/older logged arg shape falls back to a generic presentation rather than throwing. See `packages/tools` ("Tool-owned UI presentation") and `packages/acp` ("Tool-call presentation").
+These tools own how their calls render in a UI (an editor's tool-call card) via the `dsh-tools` `presentCall`/`presentResult` seam — a UI never special-cases tool names. For `bash`: the **title** is the model-written `description` followed by the exact `command` ("List files in src — ls -la src"), `kind` is `execute` (terminal/run treatment), and the `command` is ALSO the **rawInput**. Why both in the title: an execute-kind card hides `rawInput` (Zed renders it only for non-terminal tools), so the command must ride in the always-visible title to be seen — the reference ACP adapters (claude-agent-acp, codex-acp) likewise put the command in an execute tool's title. The completed output is wrapped in a fenced ` ```console ` block — a UI-only affordance, so the model-facing result text stays unfenced. `bash` also flags itself as a **terminal** (the neutral `terminal` field on its presentation: `presentCall` sets a `cwd` from an explicit absolute `workdir`, else leaves it for the UI bridge to fill from the session cwd; `presentResult` carries the output) so a capable client (Zed) renders a terminal card instead of the text block — see `packages/acp` ("Terminal card"). `bash_output`/`bash_kill` present a task-scoped title ("Read output from background task bash-3" / "Kill background task bash-3") with the task id as rawInput. These methods are pure/display-only (they also run on `session/load` replay), and a malformed/older logged arg shape falls back to a generic presentation rather than throwing. See `packages/tools` ("Tool-owned UI presentation") and `packages/acp` ("Terminal card" / "Tool-call presentation").
 
 ## Background completion notices