Prevent race conditions between `cargo run` and `npx vite build` in `tools/run`.

To reproduce:

* Make any change (even just `touch`) to a file in `ui`.
* Run `tools/run`.

There's a decent chance that the script will fail, with esoteric and variable errors:

```
failed to load config from .../pilcrow/vite.config.js_api(buil...
error when starting dev server:
Error [ERR_MODULE_NOT_FOUND]: Cannot find package '@sveltejs/kit' imported from .../pilcrow/vite.config.js.timestamp-1752608239248-52b6b8965ad28.mjs
```

is one such exmple.

These errors are due to the `npm ci` carried out by `cargo` at build time (see `build.rs`), which deletes and re-creates `node_modules`. Vite and Svelte do not like having `node_modules` deleted out from under them. As `cargo` will rerun `build.rs` any time `ui` changes, this means that `tools/run` effectively requires a complete build _first_, before it can be run.

1 files changed, 5 insertions, 1 deletions

diff --git a/tools/run b/tools/run
index 8560c31..04ae2d8 100755
--- a/tools/run
+++ b/tools/run
@@ -5,8 +5,12 @@
 ## Runs the service, and runs a development version of the UI, with hot
 ## reloading and live code changes enabled.
 
-PIDS=()
+# Stop `cargo run` and `npx vite dev` from racing with each other with
+# respect to the build output by forcing a build _first_, while neither
+# is running.
+cargo build
 
+PIDS=()
 trap 'kill "${PIDS[@]}"' EXIT
 
 cargo run &