feat: vendor and censor the phishing blocklist at build time (closes #219)

The blocklist URL in shipped code named a competitor and pointed at a moving
ref, and the extension re-fetched from it every 24 hours, which also meant a
third party decided what this wallet warns about. All of that is gone.

script/vendor-blocklist fetches upstream at a pinned commit, verifies the
sha256 of the bytes that commit serves, and writes
src/shared/phishingBlocklist.json. It is build-time tooling, never shipped, and
the one place in the repo that names the upstream project; a source reference
nobody can verify is not a source reference.

The artifact stores truncated sha256 digests rather than domain names. That is
what censors it: the previous file contained the competitor's name 6,475 times,
as phishing domains impersonating them, and not one of those domains is
dropped. It also makes lookups a binary search over a fixed-width string, so
nothing is built at module load — which matters on MV3, where the worker
re-evaluates the module on every wake — and takes the file from 8.7 MB to
1.7 MB.

script/check-censored enforces the rest: it reads the name out of the vendoring
script rather than repeating it, and fails on any occurrence in the working
tree or under dist/ that is not one of the two literals shipped code cannot
avoid. It runs in make check, which inspects dist/ when there is one and says
loudly when there is not, and again with --require-dist at the end of every
make build.

Removing the runtime fetch retires the delta, the extension-storage persistence
and the 24-hour alarm from #158. A retired alarm is now cleared rather than
left waking the worker forever on installs that already have it.

The e2e suite drives the warning end to end from a real blocklisted origin
served as a real http(s) site, with a control asserting the banner stays hidden
for one that is not listed. Its service-worker interception canary needed a new
anchor, since the startup fetch it used to watch for no longer happens: it now
wakes the worker with a message and asks it for one throwaway fetch.

LICENSE no longer cites a repository that returns 404.

eslint.config.js gains one block: script/lib/ holds node programs the shell
entrypoints call, and without it they lint with no globals at all.

TODO.md

@@ -72,6 +72,28 @@ but the review is broader than any of them.
   the deletion of both persisted-value assignments in `settings.js` (only the
   selector round-trip case red)
   ([#229](https://git.eeqj.de/sneak/AutistMask/issues/229)).
+- 2026-08-17: The phishing blocklist is vendored at build time and censored, and
+  the runtime fetch is gone
+  ([#219](https://git.eeqj.de/sneak/AutistMask/issues/219)).
+  `script/vendor-blocklist` fetches upstream at a pinned commit, verifies the
+  sha256 of the bytes it was served, and writes
+  `src/shared/phishingBlocklist.json` as truncated sha256 digests rather than
+  domain names — which is what removes the competitor's name from a list that
+  carried it 6,475 times, without dropping a single one of those domains.
+  `script/check-censored` runs in `make check` and again against `dist/` at the
+  end of every build; the name now appears only in the vendoring script, which
+  defines it once, and in the two literals shipped code cannot avoid (the
+  `isMetaMask`/`_metamask` provider shim, and one ERC-20's on-chain name).
+  Removing the fetch retired the delta, the persistence and the 24-hour alarm
+  from [#158](https://git.eeqj.de/sneak/AutistMask/issues/158), and retired
+  alarms are now cleared rather than left running on existing installs. Two
+  consequences, both deliberate: the list no longer self-updates, so it is as
+  fresh as the last vendoring run that was released; and re-vendoring from
+  current upstream took it from 231,357 stale entries to 105,721 current ones,
+  because upstream prunes and the vendored snapshot never did. `dist/` fell from
+  18.9 MB to 8.9 MB. The e2e suite now drives the warning end to end from a real
+  blocklisted origin, and its service-worker interception canary has a new
+  anchor, because the startup fetch it used to watch for no longer exists.
 - 2026-08-17: One wording for an empty password field on every screen that asks
   for one. The private key export screen said "Password is required." where the
   other five say "Please enter your password.", the same one-condition-two-
@@ -100,9 +122,10 @@ but the review is broader than any of them.
   and coverage change, not a repair of a broken target. `storageGet()` and
   `storageSet()` **reject** where `storage.local` is absent rather than
   resolving `{}` and a no-op write — they carry the wallet, and defaulting would
-  read an existing wallet back as none. The one caller that genuinely degrades,
-  [`src/shared/phishingDomains.js`](src/shared/phishingDomains.js), takes
-  `storageLocal()` directly and keeps its own null check.
+  read an existing wallet back as none. The one caller that genuinely degraded,
+  [`src/shared/phishingDomains.js`](src/shared/phishingDomains.js), took
+  `storageLocal()` directly and kept its own null check; it stores nothing at
+  all as of [#219](https://git.eeqj.de/sneak/AutistMask/issues/219) above.
 - 2026-08-17: An address total no longer reports `$0.00` for holdings it cannot
   price. Prices exist for the top 25 tokens only, so the priced-only sum was
   printed as the total and an address holding nothing but unpriced ERC-20s was