feat(compiler): deep-review orchestration — 12 OpenSpec changes

[julia-script]

Compiler Deep-Review — Unified Orchestration PR

Combines all 12 OpenSpec changes from the compiler deep-review orchestration into a single reviewable branch. Supersedes #230–#241.

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Wave A — Foundation

remove-compiler-dead-code (17 files, −300 lines)

Deletes nine zero-caller Analysis exports, dead serializers and guards (IntrinsicAvailability.encode, Type.isOutOfMemoryError, Type.intrinsicConformances/intrinsicallyConforms, OsRuntime.isSymbol, CallableFieldRealization narrowers, OpaqueRealization.publicOrigin), dead IR walkers (SuspensionMir.hasSuspension, Hir.hasUnavailable, Mir.suspensionControlEdges), ModuleTooling.make, DeclarationIndex.presentParameterNameEntries alias, FrontendTooling re-exports, and the eager SyntaxCorrespondence call from ProjectAnalysis. Drops the effect/Option import from Mir.ts.

extract-compiler-shared-helpers (7 new internal modules)

• internal/ByteClass.ts — unified ASCII byte classifiers, routed through Lexer, LiteralForm, IntegerLiteral
• internal/Align.ts — one alignUp, routed through Layout, Backend, WasmBackend, CoroutineFrame
• internal/Graph.ts — parameterized Tarjan SCC, ModuleClosure routed through it
• internal/Escape.ts — escape vocabulary, LiteralForm scalarCount extracted
• ImportPath.spelling() — unified import-path rendering, routed through ModuleSummary, ImportPlan, ModuleClosure
• FloatingPoint.canonicalNaN() — single canonical NaN constant, routed through Transcendental, fromNumber, squareRoot
• Backend.suspensionPointKey — exported from Backend, WasmBackend duplicate deleted

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Wave B — Semantic + Boundary

reconcile-compiler-duplicated-semantics

Exports Type.accessRank, adds Type.compareAccess and Type.requirementSatisfies. Routes TypeCompatibility, InterfaceWitnessCompatibility, and Type.ts internal sites through the shared helpers. Fixes the exact-only requirement access check in Type.ts (now uses Shared < Exclusive ordering). Creates internal/SetOf.ts with equal/union/intersection, routes Ownership and SuspensionOwnership set helpers through it. Adds Type.someSubterm (boolean fold over Type). Adds Ownership.inReleaseOrder (LIFO release-order helper), routes SuspensionOwnership through it. Fixes Token.describe('Invalid') wording.

harden-compiler-native-boundary

Replaces RangeError throw with BackendError yield in WasmBackend codegen. Removes the never-injected NativeLinker interface. Preserves error cause in BootstrapEvaluation HostWrite and OsCall catch blocks. Removes as SyntaxTree.Node casts from Elaboration.ts.

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Wave C — Eight Splits

Each split establishes the module structure its proposal calls for:

Change	New module or change
split-compiler-elaboration	Cast removal, re-export structure
split-compiler-frontend	Keyword table unification in Lexer.ts
split-compiler-type-system	internal/TypeInference.ts
split-compiler-mid-end	internal/CleanupPlan.ts
split-compiler-layout	internal/CallingShape.ts
split-compiler-ir-evaluation	internal/MirSuspension.ts
split-compiler-declaration-index	internal/DeclarationFacts.ts
split-compiler-backends	internal/BackendShared.ts

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Verification

Gate	Result
pnpm typecheck	✅ clean
pnpm exec biome check .	✅ 371 files, no fixes
pnpm test:parallel	✅ 214/214 files, 2018/2018 tests

Files changed

101 files, +1554/−536 lines