refactor(tests): transpile TS test suite to ReScript

Converts all six TypeScript test files under tests/ to ReScript per the
hyperpolymath language policy ("No new TypeScript files — Convert
existing TS to ReScript").  The extension runtime is untouched: TS was
only in tests/ and never shipped in the XPI (verified by unzipping
fireflag-0.1.0.zip before the change).

Files:
  tests/Bindings.res                         — Deno.test / std/assert bindings
  tests/unit/TypesTest.res                   — 23 tests (was types_test.ts)
  tests/unit/FlagEvaluationTest.res          — 19 tests
  tests/property/FlagPropertiesTest.res      — 18 tests
  tests/aspect/SecurityTest.res              — 21 tests
  tests/e2e/ExtensionLifecycleTest.res       — 13 tests
  tests/bench/FlagBench.res                  — 26 benchmarks

Wire-up:
  rescript.json   — tests/ added as a "dev" source subdir
  deno.json       — added @rescript/runtime esm.sh mapping; test tasks
                    now point at the compiled *.res.js outputs; --no-check
                    bypasses the ReScript runtime's TS-from-d.ts resolution
                    (which Deno's type-checker doesn't understand)
  .gitignore      — ignore *.cmj / *.ast, and the lib/ocaml/*.res mirror
                    the rescript compiler maintains as a cache (the four
                    historically-tracked files are explicitly kept)

Verification:
  deno task test       → 94 passed | 0 failed (611ms)
  deno task test:bench → all 26 benchmarks run

Semantic parity with the original TS suite was the only acceptance
criterion.  Heterogeneous flag values (TS `unknown`) are modelled as an
abstract type with identity coercions (toU / fromU) — zero runtime cost.
TS classes (FireflagExtension) become mutable records + top-level
functions.  The `effects`/`caps`/`loc` exclusions we applied in the
typed-wasm ECHIDNA erasure test (sibling repo) are not relevant here;
fireflag tests exercise behaviour, not proof erasure.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

.gitignore

@@ -85,6 +85,18 @@ ai-cli-crash-capture/
 *.cmt
 *.cmti
 *.cmi
+*.cmj
+*.ast
+# The rescript build mirrors each compiled source into `lib/ocaml/<Module>.res`
+# as a stable backup copy.  The canonical sources live in `extension/lib/rescript/`
+# and `tests/` (see rescript.json).  Ignore the mirror to keep git history clean.
+/lib/ocaml/*.res
+# Preserve the handful of files that ARE intentionally tracked there today
+# (historic BucklScript layout).  `git add -f` can be used for new ones.
+!/lib/ocaml/BrowserAPI.res
+!/lib/ocaml/DatabaseUpdater.res
+!/lib/ocaml/DevTools.res
+!/lib/ocaml/Types.res
 target/
 node_modules/
 _build/

deno.json

@@ -2,15 +2,16 @@
   "imports": {
     "std/": "https://deno.land/std@0.220.0/",
     "std/assert": "https://deno.land/std@0.220.0/assert/mod.ts",
-    "std/testing/": "https://deno.land/std@0.220.0/testing/"
+    "std/testing/": "https://deno.land/std@0.220.0/testing/",
+    "@rescript/runtime/": "https://esm.sh/@rescript/runtime@12.1.0/"
   },
   "tasks": {
-    "test": "deno test --allow-read tests/",
-    "test:unit": "deno test --allow-read tests/unit/",
-    "test:property": "deno test --allow-read tests/property/",
-    "test:e2e": "deno test --allow-read tests/e2e/",
-    "test:aspect": "deno test --allow-read tests/aspect/",
-    "test:bench": "deno bench tests/bench/",
-    "test:all": "deno test --allow-read tests/ && deno bench tests/bench/"
+    "test": "deno test --allow-read --no-check 'tests/**/*Test.res.js'",
+    "test:unit": "deno test --allow-read --no-check 'tests/unit/*Test.res.js'",
+    "test:property": "deno test --allow-read --no-check 'tests/property/*Test.res.js'",
+    "test:e2e": "deno test --allow-read --no-check 'tests/e2e/*Test.res.js'",
+    "test:aspect": "deno test --allow-read --no-check 'tests/aspect/*Test.res.js'",
+    "test:bench": "deno bench --no-check 'tests/bench/*Bench.res.js'",
+    "test:all": "deno test --allow-read --no-check 'tests/**/*Test.res.js' && deno bench --no-check 'tests/bench/*Bench.res.js'"
   }
 }

rescript.json

@@ -4,6 +4,11 @@
     {
       "dir": "extension/lib/rescript",
       "subdirs": true
+    },
+    {
+      "dir": "tests",
+      "subdirs": true,
+      "type": "dev"
     }
   ],
   "package-specs": [

tests/Bindings.res

@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: PMPL-1.0-or-later
+// Copyright (c) 2026 Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
+//
+// Bindings for the Deno test runtime and the `std/assert` module used by
+// the fireflag test suites.  The paths `"std/assert"` and `"std/testing/..."`
+// are resolved via the import map in `deno.json`.
+//
+// Kept terse — each binding is the minimum surface the test suites use.
+
+// ── Deno.test ────────────────────────────────────────────────────────────
+
+@scope("Deno") @val
+external test: (string, unit => unit) => unit = "test"
+
+@scope("Deno") @val
+external testAsync: (string, unit => promise<unit>) => unit = "test"
+
+// ── Deno.bench ───────────────────────────────────────────────────────────
+
+@scope("Deno") @val
+external bench: (string, unit => unit) => unit = "bench"
+
+// ── std/assert ───────────────────────────────────────────────────────────
+
+@module("std/assert")
+external assertEquals: ('a, 'a) => unit = "assertEquals"
+
+@module("std/assert")
+external assertEqualsMsg: ('a, 'a, string) => unit = "assertEquals"
+
+@module("std/assert")
+external assertStrictEquals: ('a, 'a) => unit = "assertStrictEquals"
+
+@module("std/assert")
+external assertExists: 'a => unit = "assertExists"
+
+@module("std/assert")
+external assertNotEquals: ('a, 'a) => unit = "assertNotEquals"
+
+@module("std/assert")
+external assertThrows: (unit => 'a) => unit = "assertThrows"
+
+@module("std/assert")
+external assertThrowsMsg: (unit => 'a, string) => unit = "assertThrows"
+
+@module("std/assert")
+external assertMatch: (string, Js.Re.t) => unit = "assertMatch"
+
+@module("std/assert")
+external assertStringIncludes: (string, string) => unit = "assertStringIncludes"
+
+@module("std/assert")
+external assertRejects: (unit => promise<'a>) => promise<unit> = "assertRejects"
+
+@module("std/assert")
+external assert_: bool => unit = "assert"
+
+@module("std/assert")
+external assertMsg: (bool, string) => unit = "assert"
+
+// ── std/testing/bdd (optional) ───────────────────────────────────────────
+
+@module("std/testing/bdd.ts")
+external describe: (string, unit => unit) => unit = "describe"
+
+@module("std/testing/bdd.ts")
+external it: (string, unit => unit) => unit = "it"