Run prettier across the repo, exclude the lockfile from it

Prettier had never been run in --check mode here before, so this had
drifted across most files (markdown tables, long option() chains,
line wrapping). Purely formatting, no logic changes - needed so a CI
format:check gate can actually pass. Adds .prettierignore for
pnpm-lock.yaml specifically: prettier's YAML formatter rewrites every
quoted key (single -> double quotes) producing an ~8700-line diff of
pure noise on a file pnpm itself owns the formatting of.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/cli/lib/systemd.test.ts

@@ -5,7 +5,8 @@ import { renderUnit } from "./systemd";
 test("renderUnit builds an absolute-path ExecStart with the given args", () => {
   const unit = renderUnit({
     execPath: "/usr/bin/node",
-    binPath: "/home/user/.local/share/pnpm/global/5/node_modules/.bin/triggershell",
+    binPath:
+      "/home/user/.local/share/pnpm/global/5/node_modules/.bin/triggershell",
     configPath: "/home/user/project/triggershell.yml",
     configDir: "/home/user/project",
     port: 8080,
@@ -31,5 +32,8 @@ test("renderUnit uses multi-user.target for the system scope", () => {
   });
 
   assert.match(unit, /WantedBy=multi-user\.target/);
-  assert.match(unit, /ExecStart=\/usr\/bin\/node .*start --config .*--no-browser$/m);
+  assert.match(
+    unit,
+    /ExecStart=\/usr\/bin\/node .*start --config .*--no-browser$/m,
+  );
 });