feat(teams): add text command parity

[NeoHsu]

Important

Stacked draft: logical base stack/teams-09-formatting-long-messages is PR #1501. GitHub requires an upstream PR base to exist in openabdev/openab, so this draft temporarily targets main and may show preceding stack layers. Do not merge it until #1501 is merged and this branch is rebased onto current main; then review only its single incremental commit.

What problem does this solve?

Provide one platform-neutral Core command service for /models, /agents,
/cancel, /reset, /cancel-all, and /usage; give Teams safe text-command
parity through ordinary authenticated messages; preserve Discord native UX; and
publish a conservative manifest command menu without bypassing trust, privacy,
or negotiated delivery semantics.

Discord Discussion URL: https://discord.com/channels/1491295327620169908/1491365158868619404/1531339032527765655
Microsoft Teams roadmap discussion.

Review Contract

This is the proposed PR-body contract. It is not frozen until the owner or a
maintainer approves it and records the reviewed head plus an immutable contract
revision or hash.

Goal

Provide one platform-neutral Core command service for /models, /agents,
/cancel, /reset, /cancel-all, and /usage; give Teams safe text-command
parity through ordinary authenticated messages; preserve Discord native UX; and
publish a conservative manifest command menu without bypassing trust, privacy,
or negotiated delivery semantics.

Non-goals

/remind, /auth, /export, /new, arbitrary agent slash commands, Slack
native slash delivery, Adaptive Cards, invoke activities, message extensions,
targeted messages, proactive messaging, cron, Graph, RSC, delegated tokens, new
permissions, a Gateway protocol bump, or a provider-general billing API are outside PR 10.

Accepted Residual Risks

Teams command responses are ordinary visible activities outside Personal chat;
therefore /usage is denied rather than displayed on those surfaces. An
installed manifest does not update until an operator packages and installs a
new version. Old Core deployments retain the existing partial command set.
/reset and /cancel-all remain immediate destructive controls without a new
confirmation dialog, matching existing Discord behavior. Text config lists show
at most 25 entries even when the active backend exposes more; exact-name setting
still validates against the complete option set.

Acceptance Criteria

The six canonical commands share one semantic service; Teams executes them only
after structural, L2, L3, and authenticated mention handling; Discord native
interactions use the same semantics after their existing admission; recognized
commands never reach the agent or materialize attachments; /usage cannot call
the backend or disclose data on a public or unproven-private surface;
/cancel-all and /reset clear every dispatcher lane in only the addressed
logical thread; Standalone command responses cannot deadlock the WebSocket
reader and obey negotiated send outcomes without retry; Unified and Standalone
are semantically equivalent; compatibility forms and old-peer behavior do not
regress; and the v1.25 manifest menu validates without targeted-message or new
permission fields.

Follow-ups

Evaluate Teams targeted/private messages under a separate trust and routing ADR;
add Adaptive Card interactions only after JWT/scope/identity admission is
specified for callbacks; consider a broader command registry if the core set
expands; evaluate provider-neutral usage reporting; add /remind, /auth, and
/export as separately reviewed slices.

At a Glance

Authenticated Teams activity / operator target
                    │
                    ▼
            [this PR’s bounded layer]
                    │
                    ▼
          explicit outcome or fail-closed stop

Prior Art & Industry Research

OpenClaw: its Microsoft Teams extension separates access checks, Bot Framework route context, and outbound operations. For this slice the relevant comparison is channel command admission and platform-neutral command semantics.

Hermes Agent: its Teams platform adapter keeps Teams-specific transport and message shaping behind a platform adapter. It does not provide OpenAB’s negotiated Core/Gateway outcome contract, so this PR keeps the useful adapter boundary but adds explicit fail-closed semantics.

Proposed Solution

• Add a shared Core command service and authenticated Teams text-command parity.
• Keep recognized commands ahead of attachment, session, and agent side effects.
• Add and validate a conservative Microsoft Teams v1.25 manifest fixture and command menu.

Why this approach?

A shared semantic service prevents Teams and Discord command behavior from drifting while preserving each platform’s admission and UX.

Alternatives Considered

Implement a Teams-only command stack (rejected: semantic drift) or expose /usage in groups (rejected: privacy risk).

Validation

• cargo check -p openab-core
• cargo check -p openab-gateway --features teams
• cargo test --manifest-path crates/platform-schema/Cargo.toml