chore(slint): add slint-run.sh dev helper (run prebuilt binary directly)

Builds in release then execs crates/target/release/qbz-slint directly instead of
via 'cargo run', so process monitors show it as 'qbz-slint' (a cargo-run child
inherits CARGO_* env and shows as 'cargo'), cleanly separate from the build
processes. Same release flags as slint-dev.sh.

cc

(cherry picked from commit 41269aabbe)

scripts/slint-run.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+# QBZ Slint — build with cargo, then run the BINARY DIRECTLY.
+#
+# Why this exists (vs slint-dev.sh which does `cargo run`): `cargo run` launches
+# the app as a cargo-managed run target — the process inherits CARGO_* env and a
+# cargo launch context, which KDE plasma-systemmonitor surfaces by labelling the
+# RUNNING APP as "cargo" instead of "qbz-slint" (the kernel comm is still
+# qbz-slint; it's only the monitor's display name). Running the prebuilt binary
+# directly (no cargo wrapper) makes process monitors show it as `qbz-slint`,
+# cleanly separate from the cargo/rustc BUILD processes.
+#
+# Same RELEASE build + flags as slint-dev.sh (the produced binary is identical);
+# only the launch differs. Use slint-dev.sh for quick build+run iteration; use
+# this when you want the running process to read as `qbz-slint` in the monitor.
+#
+# Usage: ./scripts/slint-run.sh [extra app args]
+#        THREADS=16 ./scripts/slint-run.sh   # override frontend threads
+set -euo pipefail
+cd "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/.."
+# Keep in sync with slint-dev.sh / .cargo/config.toml (RUSTFLAGS overrides, not
+# merges, the config rustflags — so re-list the AES-NI/SSSE3 features).
+export RUSTFLAGS="-C target-feature=+aes,+ssse3 -C link-arg=-fuse-ld=mold -Z threads=${THREADS:-16}"
+cargo +nightly build --release --manifest-path crates/Cargo.toml -p qbz-slint
+# exec the binary directly — no `cargo run`, so no CARGO_* env / cargo context,
+# so the monitor shows `qbz-slint`.
+exec crates/target/release/qbz-slint "$@"