fix(#999): resolve all clippy warnings across the workspace

All crates now pass `cargo clippy --workspace -- -D warnings` cleanly.

Fixes span six crates (hive-sh4re, hive-ag3nt, hive-c0re, hive-forge,
hive-priv, hive-matrix-mcp was already clean):

- doc_markdown: wrap snake_case, type names, constants in backticks
- collapsible_if / collapsible_match: fold nested ifs into let-chains
- duration_suboptimal_units: Duration::from_secs(N) → from_mins/from_hours
- implicit_hasher: allow on HashMap-param fns where generalization is risky
- items_after_statements: hoist use to function tops
- map(f).unwrap_or(x) → map_or(x, f); map(f).unwrap_or_else(g) → map_or_else
- is_ok_and / is_none_or in place of map().unwrap_or(bool)
- needless_continue: {} instead of continue in loop match arms
- match_same_arms: Ok(None) | Err(_) merged
- format_push_str: write!() instead of push_str(&format!())
- while let replaces loop { let Some(..) = x else { break } }
- struct_excessive_bools / dead_code: allow on purpose-built structs
- too_many_lines / too_many_arguments: allow where refactor not worth it
- unused_async: remove async from poll_once in bash_runner
- needless_borrow: fix &repo deref in hive-forge comments verb
- cast_possible_truncation: allow u64→usize in fetch_tail

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

hive-c0re/src/dashboard.rs

@@ -159,6 +159,7 @@ fn try_bind(addr: SocketAddr) -> std::io::Result<tokio::net::TcpListener> {
     sock.listen(1024)
 }
 
+#[allow(clippy::struct_excessive_bools)]
 #[derive(Serialize)]
 struct StateSnapshot {
     /// Broker seq at the moment this snapshot was assembled. Clients
@@ -1833,7 +1834,7 @@ async fn get_build_log_stream(
             match notify_rx.recv().await {
                 // Notification for a different build — ignore and wait
                 // for the next one.
-                Ok(notif_id) if notif_id != id => continue,
+                Ok(notif_id) if notif_id != id => {}
                 Ok(_) => {
                     match logs.get_progress(id, stdout_cursor, stderr_cursor) {
                         Ok(Some(prog)) => {
@@ -1845,20 +1846,17 @@ async fn get_build_log_stream(
                                 stderr_append: prog.stderr_append,
                                 status: prog.status,
                                 done,
-                            }) {
-                                if tx.send(Ok(Event::default().data(json))).await.is_err() {
-                                    return; // browser disconnected
-                                }
+                            }) && tx.send(Ok(Event::default().data(json))).await.is_err() {
+                                return; // browser disconnected
                             }
                             if done {
                                 return;
                             }
                         }
-                        Ok(None) => return, // vacuum reaped the row
-                        Err(_) => return,
+                        Ok(None) | Err(_) => return, // vacuum reaped row / channel closed
                     }
                 }
-                Err(tokio::sync::broadcast::error::RecvError::Lagged(_)) => continue,
+                Err(tokio::sync::broadcast::error::RecvError::Lagged(_)) => {}
                 Err(tokio::sync::broadcast::error::RecvError::Closed) => return,
             }
         }