docs(install): add help for --force option of install command (#3878)

ref #1906

.changeset/kind-beers-doubt.md

@@ -0,0 +1,5 @@
+---
+"@pnpm/plugin-commands-installation": patch
+---
+
+add help for `--force` option of `install` command (re: #3878)

packages/plugin-commands-installation/src/install.ts

@@ -204,6 +204,10 @@ by any dependencies, so it is an emulation of a flat node_modules',
             description: 'Clone (aka copy-on-write) packages from the store',
             name: '--package-import-method clone',
           },
+          {
+            description: 'Force reinstall dependencies: refetch packages modified in store, recreate a lockfile and/or modules directory created by a non-compatible version of pnpm',
+            name: '--force',
+          },
           ...UNIVERSAL_OPTIONS,
         ],
       },