proto becomes bxcore, the one shared crate (M5b task 00)

Done the way the owner asked and the spike mapped: the crate and the
manifests renamed, then what the build reported fixed. Layers: 138
"proto unresolved" errors across 169 files; cargo fmt reordering
imports; six fixture paths built as strings in brokerd's and bxctl's
tests, which the compiler cannot see, and comments naming
crates/proto/; the crate-dependency check and its self-test. One more
the spike did not reach: a `\nproto =` key inside a printf format in
the self-test, which a word-boundary replacement skips because `n` and
`p` are both word characters.

make gate: gate: ok, 944 tests; no new entry in /tmp.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

crates/brokerd/tests/support/audit_dir.rs

@@ -6,7 +6,7 @@ use std::collections::BTreeMap;
 use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicU32, Ordering};
 
-use proto::{AuditEvent, CallId, DataClass, DecisionRecord, SessionId, Timestamp};
+use bxcore::{AuditEvent, CallId, DataClass, DecisionRecord, SessionId, Timestamp};
 
 pub const D1: &str = "2026-09-17.jsonl";
 pub const D2: &str = "2026-09-18.jsonl";
@@ -28,14 +28,14 @@ impl TempDir {
         TempDir { path }
     }
 
-    /// A copy of the fixture log `case` from `crates/proto/tests/fixtures/audit/`. With `only`,
+    /// A copy of the fixture log `case` from `crates/bxcore/tests/fixtures/audit/`. With `only`,
     /// just those files: damage in an older file is not seen by an ordinary start, so tests of
     /// the startup check copy the damaged file alone.
     pub fn case(case: &str, only: Option<&[&str]>) -> TempDir {
         let dir = TempDir::unmade(case);
         std::fs::create_dir_all(&dir.path).unwrap();
         let from = format!(
-            "{}/../proto/tests/fixtures/audit/{case}",
+            "{}/../bxcore/tests/fixtures/audit/{case}",
             env!("CARGO_MANIFEST_DIR")
         );
         let mut copied = 0;
@@ -88,7 +88,7 @@ pub fn denied(call: u64) -> AuditEvent {
         tool: "read_file".to_string(),
         arguments: r#"{"path":"/etc/hosts"}"#.to_string(),
         outcome: DecisionRecord::Denied {
-            reason: proto::DenyReason::NoGrant,
+            reason: bxcore::DenyReason::NoGrant,
         },
         grant: None,
         grant_sha256: None,

crates/brokerd/tests/support/build.rs

@@ -6,7 +6,7 @@
 
 use brokerd::grants::{GrantSet, LoadedGrant};
 use brokerd::policy::{Ask, Decision, Denial, Outcome, SessionState};
-use proto::{
+use bxcore::{
     CallId, Constraints, DataClass, DenyReason, Grant, Mode, SessionId, Timestamp, ToolRequest,
 };
 
@@ -39,7 +39,7 @@ pub fn grant(id: &str, tool: &str, mode: Mode) -> Build {
             constraints: Constraints::default(),
         },
         // Stands in for the file's hash, and differs from grant to grant.
-        sha256: proto::sha256(id.as_bytes()).unwrap(),
+        sha256: bxcore::sha256(id.as_bytes()).unwrap(),
     })
 }
 

crates/brokerd/tests/support/client.rs

@@ -11,7 +11,7 @@ use std::sync::Arc;
 use std::time::Duration;
 
 use brokerd::broker::{self, Broker};
-use proto::{Envelope, Message, PROTOCOL_VERSION, ToolRequest};
+use bxcore::{Envelope, Message, PROTOCOL_VERSION, ToolRequest};
 
 use crate::rig::Rig;
 use crate::runtime::{Recording, Shared};
@@ -49,7 +49,7 @@ pub fn open(
         r#final: true,
         msg,
     };
-    proto::write_frame(&mut client, &env).unwrap();
+    bxcore::write_frame(&mut client, &env).unwrap();
     client
 }
 
@@ -60,7 +60,7 @@ pub fn next(stream: &mut UnixStream) -> Envelope {
         let peer_closed = cfg!(target_vendor = "apple") && e.raw_os_error() == Some(22);
         assert!(peer_closed, "set_read_timeout: {e}");
     }
-    proto::read_frame(stream).unwrap()
+    bxcore::read_frame(stream).unwrap()
 }
 
 /// Sends a tool request to `broker::handle` and reads every frame up to the final one.

crates/brokerd/tests/support/fake_gateway.rs

@@ -8,7 +8,7 @@ use std::path::{Path, PathBuf};
 use std::sync::mpsc::{self, Receiver};
 use std::time::Duration;
 
-use proto::{
+use bxcore::{
     ApprovalPosted, ApprovalReply, Envelope, ErrorCode, GatewayOutcome, Message, PROTOCOL_VERSION,
     PendingApproval, WireError, read_frame, write_frame,
 };
@@ -141,7 +141,10 @@ impl Conn {
     /// Did the courier close the connection within `wait`, without sending anything?
     pub fn closed_within(&mut self, wait: Duration) -> bool {
         self.stream.set_read_timeout(Some(wait)).unwrap();
-        matches!(read_frame(&mut self.stream), Err(proto::FrameError::Closed))
+        matches!(
+            read_frame(&mut self.stream),
+            Err(bxcore::FrameError::Closed)
+        )
     }
 
     pub fn close(self) {

crates/brokerd/tests/support/oracle.rs

@@ -10,7 +10,7 @@
 
 use brokerd::grants::LoadedGrant;
 use brokerd::policy::SessionState;
-use proto::{
+use bxcore::{
     CallId, Constraints, DataClass, DenyReason, Grant, Mode, SessionId, Timestamp, ToolRequest,
 };
 
@@ -119,7 +119,7 @@ pub fn some_grant(rng: &mut Rng, id: usize) -> LoadedGrant {
             secret: None,
             constraints,
         },
-        sha256: proto::sha256(format!("file {id}").as_bytes()).unwrap(),
+        sha256: bxcore::sha256(format!("file {id}").as_bytes()).unwrap(),
     }
 }
 

crates/brokerd/tests/support/rig.rs

@@ -12,7 +12,7 @@ use brokerd::audit::Writer;
 use brokerd::config::{Approvals, Config, Paths, Sockets};
 use brokerd::ledger::Ledger;
 use brokerd::state::StateStore;
-use proto::{AuditEvent, AuditRecord, CallId, SessionId, ToolRequest};
+use bxcore::{AuditEvent, AuditRecord, CallId, SessionId, ToolRequest};
 
 use crate::sink::{Flaky, Lines, Switch};
 use crate::tmp::TempDir;

crates/brokerd/tests/support/sink.rs

@@ -9,7 +9,7 @@ use std::sync::{Arc, Mutex};
 
 use brokerd::audit::{AuditError, Writer};
 use brokerd::ledger::AuditSink;
-use proto::{AuditEvent, Timestamp};
+use bxcore::{AuditEvent, Timestamp};
 
 /// Switches shared between a test and its `Flaky` sink.
 #[derive(Clone, Default)]