--available-tools and --excluded-tools flags silently ignored in ACP mode (--acp)

[catatafishen]

Describe the bug

When running the CLI in ACP mode (--acp), the --available-tools and
--excluded-tools flags have no effect. The flags are parsed correctly but
never applied to the session — the model sees the full tool list regardless.

Affected version

1.0.34

Steps to reproduce the behavior

copilot --acp --stdio --excluded-tools bash edit view
The model can still call bash, edit, view etc. as if the flags were not
passed.

Expected behavior

--available-tools foo bar restricts the model to only foo and bar.
--excluded-tools bash edit hides bash and edit from the model's tool
list, matching the behaviour in interactive and non-interactive modes.

Additional context

Root cause (source-located)

In index.js, the ACP startup path branches and returns early before
availableTools/excludedTools are applied:

// Line ~4375 (main command handler)
if (t.acp) {
await startACPMode({ ..., options: t, rules: E, ... }, authManager)
return // ← early exit; ae/ce computed below never run
}
ae = normalise(t.availableTools) // only reached for interactive/non-interactive
ce = normalise(t.excludedTools)

The raw CLI options object t is forwarded as options: t, so
this.options.options.availableTools / this.options.options.excludedTools are
accessible inside the Jpt class. However, Jpt.newSession() and
Jpt.loadSession() never read them:

// Jpt.newSession — current code
let l = await this.sessionManager.createSession({ sessionId, workingDirectory, ... })
this.mcpHost && l.updateOptions({ mcpServers: ..., mcpHost: ... })
// ← availableTools / excludedTools never set

Compare to interactive mode (Mto) and non-interactive mode (Cul), both of
which correctly call:

session.updateOptions({ ..., availableTools: s, excludedTools: l, ... })

Minimal fix

In Jpt.newSession() and Jpt.loadSession(), after the existing
updateOptions call for mcpHost, add:

const _opts = this.options.options

if (_opts?.availableTools || _opts?.excludedTools)

session.updateOptions({

availableTools: _opts.availableTools,

excludedTools: _opts.excludedTools

})

Workaround

--deny-tool does work in ACP mode because it populates rules.denied, which
is passed to createSessionPermissionService and consulted before any
session/request_permission is sent to the ACP client. However, this only
controls the permission layer — the tools still appear in the model's tool list.