unhack: add pre-commit guidelines (#19617)

.pre-commit-config.yaml

@@ -3,14 +3,29 @@
 
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
+#
+# Opt-in to running pre-commit hooks by running `make tools`.
+#
+# Guidelines for adding new pre-commit hooks
+# ====================================================================
+# A hook SHOULD be blazingly fast (<2s) to impose minimal latency on
+# developer workflows (e.g. golangci-lint takes > 8s)
+#
+# A hook SHOULD attempt to fix errors, not just identify them.
+#
+# A hook SHOULD address common errors in files that tend to change
+# frequently. While surfacing esoteric issues is nice, hooks that have a
+# wider impact are preferred.
+#
 repos:
 -   repo: https://github.com/tekwizely/pre-commit-golang
     rev: v1.0.0-rc.1
     hooks:
-    # Formats go imports into deterministic sections
-    # `pre-commit run gci` to run in isolation
+    # Formats go imports into deterministic sections.
+    # `pre-commit run gci` to run in isolation.
     -   id: my-cmd
-        name: gci
+        name: Format go imports
+        alias: gci
         # skip all generated go files
         exclude: |
             (?x)(