fix: unbreaks postgrest-profiled-run

* replaces v2-build -> v2-run (which should be v2-exec)
  with one-shot v2-run
* fixes empty postgrest.prof file by sending SIGINT to the profiled
  postgrest process to trigger writing it explicitly

nix/tools/cabalTools.nix

@@ -95,9 +95,8 @@ let
         export PGRST_DB_POOL_ACQUISITION_TIMEOUT
         export PGRST_JWT_SECRET
 
-        ${cabal-install}/bin/cabal --builddir="dist-prof" v2-build --enable-profiling --disable-shared exe:postgrest
-        ${cabal-install}/bin/cabal --builddir="dist-prof" v2-run -- \
-          postgrest +RTS -p -h -RTS "''${_arg_leftovers[@]}"
+        exec ${cabal-install}/bin/cabal --builddir="dist-prof" v2-run --enable-profiling --disable-shared exe:postgrest -- \
+          +RTS -p -h -RTS "''${_arg_leftovers[@]}"
       '';
 
   repl =

nix/tools/withTools.nix

@@ -5,6 +5,7 @@
 , lib
 , postgresqlVersions
 , postgrest
+, procps
 , python3Packages
 , slocat
 , writeText
@@ -373,6 +374,14 @@ let
         pid=$!
         # shellcheck disable=SC2317
         cleanup() {
+          # Send INT to all postgrest processes.
+          # Workaround to trigger dumping postgrest.prof for postgrest-profiled-run
+          # Caveat: we cannot realistically limit this to the current process' tree,
+          # since pkill's --parent supports only direct children; therefore this
+          # would reap neighbor postgrest instances as well, because INT is asking
+          # the process to terminate too.
+          # TODO: consider cgroups to make this cleaner
+          ${procps}/bin/pkill --echo --signal=INT --exact postgrest
           kill "$pid" || true
         }
         trap cleanup EXIT