feat(cli): rm, and Delete in the interactive mode

rm deletes files, resolved as get resolves paths and patterns, with the
node's rule (design §5.4): the uploading account's devices, or the node's
operator account. The whole run is checked against the index first (the
entry's uploader_id, the role the join result gives this key): a file
outside the rule, or a folder, refuses it before anything is asked or sent.
Then one confirmation, or --yes. The node's challenge is checked against
what was asked before it is signed. In the interactive mode, Delete on the
right pane does the same, asked once per batch.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

2 files changed, 52 insertions, 2 deletions

diff --git a/packages/meshbay-cli/src/meshbay_cli/client/remove.py b/packages/meshbay-cli/src/meshbay_cli/client/remove.py
new file mode 100644
index 0000000..370cf95
--- /dev/null
+++ b/packages/meshbay-cli/src/meshbay_cli/client/remove.py
@@ -0,0 +1,45 @@
+"""
+Deleting a file from a group (docs/MESHBAY_DESIGN.md §5.4).
+
+The node decides, and on two grounds only: a key paired with it as operator, or
+a live device of the account that uploaded the file — any of them, so a file
+sent from a phone is deleted from the laptop. Being the group's owner on the hub
+is neither. The request is answered with a challenge the client signs with its
+key on the node; the node rebuilds what was signed itself.
+"""
+
+from meshbay_common import MNP_VERSION
+from meshbay_common.adminop import OP_FILE_DELETE, admin_transcript
+
+from ..errors import NODE, CliError
+from .keys import b64, unb64
+from .session import GroupSession
+
+
+def may_delete(session: GroupSession, entry: dict, user_id: str) -> bool:
+    """What the node will accept, known before asking: the operator, or the
+    file's uploader. The node checks again; this only avoids asking in vain."""
+    return session.role == "operator" or entry.get("uploader_id") == user_id
+
+
+async def delete_file(session: GroupSession, file_id: str) -> None:
+    """Delete one file. Raises `NodeRefusal` with the node's reason."""
+    reply = await session.ch.request({"type": "file_delete", "v": MNP_VERSION,
+                                      "file_id": file_id},
+                                     "admin_challenge", "file_delete_ack")
+    if reply["type"] == "file_delete_ack":
+        return
+    # What is signed is checked against what was asked, never taken from the
+    # node: a challenge for another operation, file, group or node is refused.
+    if (reply.get("op") != OP_FILE_DELETE or reply.get("subject") != file_id
+            or reply.get("group_id") != session.group_id
+            or reply.get("node_pk") != session.node_pk):
+        raise CliError(NODE, "The node asked to sign something other than this deletion; "
+                             "nothing was signed.")
+    transcript = admin_transcript(op=OP_FILE_DELETE, node_pk_b64=session.node_pk,
+                                  group_id=session.group_id, subject=file_id,
+                                  nonce=unb64(reply["nonce"]), ts=int(reply["ts"]))
+    await session.ch.request({"type": "admin_response", "v": MNP_VERSION,
+                              "op_id": reply["op_id"], "op": OP_FILE_DELETE,
+                              "signature": b64(session.identity.sk_ed.sign(transcript))},
+                             "file_delete_ack")
diff --git a/packages/meshbay-cli/src/meshbay_cli/client/session.py b/packages/meshbay-cli/src/meshbay_cli/client/session.py
index d5264a2..41bf0d6 100644
--- a/packages/meshbay-cli/src/meshbay_cli/client/session.py
+++ b/packages/meshbay-cli/src/meshbay_cli/client/session.py
@@ -197,7 +197,8 @@ class GroupSession:
 
     def __init__(self, pc: RTCPeerConnection, ch: Channel, group_id: str,
                  node_id: str, node_pk: str, gek: bytes, ack: dict,
-                 identity: Identity | None = None, nonce_node: bytes = b""):
+                 identity: Identity | None = None, nonce_node: bytes = b"",
+                 role: str = ""):
         self.pc = pc
         self.ch = ch
         self.group_id = group_id
@@ -209,6 +210,10 @@ class GroupSession:
         # and the nonce that ties a signature to this connection.
         self.identity = identity
         self.nonce_node = nonce_node
+        # What the node's roster says this key is here: "operator" when it was
+        # paired with the node — the authority to delete anyone's file. Not the
+        # hub's word on who owns the group (docs/MESHBAY_DESIGN.md §3.3).
+        self.role = role
 
     async def index(self) -> dict:
         """`{version, entries, dirs, roots}`, opened under the group key."""
@@ -351,7 +356,7 @@ async def _handshake(account: Account, pc, ch: Channel, group_id: str, node_id:
     await _device_hello(account, ch, identity, node_pk, group_id, nonce_s)
     await _settle_bundle(account, ch, identity, node_pk, bundle)
     return GroupSession(pc, ch, group_id, node_id, node_pk, gek, config,
-                        identity, nonce_s)
+                        identity, nonce_s, str(joined.get("role") or ""))
 
 
 async def _fetch_bundle(ch: Channel) -> str: