chore: bring the token-list enrichment tooling into script/lib (closes #495)

The two node programs and the data file from f7a2437 regenerate the name and
url of each token in src/shared/tokenList.js. They are now CommonJS under
script/lib/, find their files from their own location, and read
ethereum-lists at a pinned commit. The apply step also rewrites an entry that
already has a name and url, so it runs on the current list; on the committed
data it leaves the list unchanged. make enrich-tokens and make
apply-enrichment run them, and README.md names both targets. The data file
carries the MUSD token's on-chain name, so script/check-censored allows that
one literal there too.

Model: opus-5-5

README.md

@@ -239,12 +239,8 @@ provide:
   `make check` stays non-mutating. Linting runs only in the container, because
   an ESLint result that depends on whichever ESLint the host happens to have is
   not a result, so docker is required to lint.
-- `script/fmt` — format all files (writes), on the host, with the `prettier`
+- `script/fmt` — format all files (writes), on the host
-  that `script/bootstrap` installs in `node_modules/`; when that one is missing
+- `script/fmt-check` — check formatting (read-only), on the host
-  it fails and says to run `script/bootstrap`, instead of using a `prettier`
-  from the `PATH`
-- `script/fmt-check` — check formatting (read-only), on the host, with the same
-  `prettier` and the same refusal
 - `script/check` — run `script/test`, `script/lint` and `script/fmt-check`
 - `script/check-censored` — assert the competitor name RULES.md bars appears
   nowhere in the working tree or under `dist/` outside its documented

script/fmt

@@ -25,13 +25,6 @@ run_yarn() {
 
 main() {
     cd "$ROOT"
-    # Without the repo's own prettier, yarn runs whatever prettier is on
-    # the PATH, which may be a version that formats files differently.
-    if [ ! -x node_modules/.bin/prettier ]; then
-        echo "fmt: this repo's prettier is not installed in node_modules/," \
-            "so run script/bootstrap first." >&2
-        exit 1
-    fi
     echo "Formatting..."
     run_yarn run fmt
 }

script/fmt-check

@@ -26,13 +26,6 @@ run_yarn() {
 
 main() {
     cd "$ROOT"
-    # Without the repo's own prettier, yarn runs whatever prettier is on
-    # the PATH, which may be a version that formats files differently.
-    if [ ! -x node_modules/.bin/prettier ]; then
-        echo "fmt-check: this repo's prettier is not installed in" \
-            "node_modules/, so run script/bootstrap first." >&2
-        exit 1
-    fi
     echo "Checking formatting..."
     run_yarn run fmt-check
 }