REPO_POLICIES: name examples/ in README, correct the lint example's link

As #159 (comment) says.

- `README.md`: Design names `examples/`.
- `prompts/REPO_POLICIES.md`: the sentence linking
  `examples/go-lint-system-libraries.Dockerfile` says the file holds the
  first lines of a lint phase.
- `TODO.md`: 7,265 words after that sentence.

Model: opus-5-5

TODO.md

@@ -22,7 +22,7 @@ fmt-check, and commit.
 # Completed Steps
 
 - 2026-11-09: Compacted `prompts/REPO_POLICIES.md` from 1,165 lines and 8,556
-  words to 973 lines and 7,261 words
+  words to 973 lines and 7,265 words
   (https://git.eeqj.de/sneak/prompts/issues/158). Every rule keeps its meaning.
   The rules now sit under headings, the pinning rule first. Each rule that was
   stated in several places is stated once. The Makefile copies of the Go and