feat: update watr v4.3.0 feature support (#533)

Adds features introduced in watr v4.3.0:

- **Custom Descriptors** (Phase 3) — `descriptor`/`describes` types,
`exact` heap types, new descriptor cast/branch instructions
- **Stack Switching** (Phase 3) — `cont` type, `cont.new`, `cont.bind`,
`suspend`, `resume`, `resume_throw`, `switch`
- **Custom Page Sizes** (Phase 3) — `(pagesize N)` attribute on memory
declarations
- **Compact Import Section** (Phase 3) — grouped `(import "mod" (item
…)*)` syntax
- **Numeric Values in WAT** (Phase 2) — typed
`i8`/`i16`/`i32`/`i64`/`f32`/`f64` values in data segments

Also adds missing entries for features not supported (`exceptions:
false`, `compilationHints: null`, `extendedNameSection: null`).

Author: dy

features.json

@@ -873,10 +873,16 @@
         "bigInt": true,
         "branchHinting": true,
         "bulkMemory": true,
+        "compactImportSection": true,
+        "compilationHints": null,
         "customAnnotationSyntaxInTheTextFormat": true,
+        "customDescriptors": true,
+        "customPageSizes": true,
         "esmIntegration": null,
+        "exceptions": false,
         "exceptionsFinal": true,
         "extendedConst": true,
+        "extendedNameSection": null,
         "gc": true,
         "jsPrimitiveBuiltins": null,
         "jsStringBuiltins": true,
@@ -885,11 +891,13 @@
         "multiMemory": true,
         "multiValue": true,
         "mutableGlobals": true,
+        "numericValuesInWat": true,
         "referenceTypes": true,
         "relaxedSimd": true,
         "saturatedFloatToInt": true,
         "signExtensions": true,
         "simd": true,
+        "stackSwitching": true,
         "tailCall": true,
         "threads": true,
         "typedFunctionReferences": true,