chore: VQL -> VCL rename completion (src/vcl/*.res + docs)

Completes the 2026-04-12 VQL -> VCL rename that was left uncommitted
(memory rule vcl-rename.md). 11 source files renamed:

  src/vcl/VQLBidir.res          -> VCLBidir.res
  src/vcl/VQLCircuit.res        -> VCLCircuit.res
  src/vcl/VQLContext.res        -> VCLContext.res
  src/vcl/VQLError.res          -> VCLError.res
  src/vcl/VQLExplain.res        -> VCLExplain.res
  src/vcl/VQLParser.res         -> VCLParser.res
  src/vcl/VQLParser_test.res    -> VCLParser_test.res
  src/vcl/VQLProofObligation.res -> VCLProofObligation.res
  src/vcl/VQLSubtyping.res      -> VCLSubtyping.res
  src/vcl/VQLTypeChecker.res    -> VCLTypeChecker.res
  src/vcl/VQLTypes.res          -> VCLTypes.res

Plus two doc touch-ups:
  docs/backwards-compatibility.adoc: `VeriSim.VQLCompatibilityTest`
    -> `VeriSim.VCLCompatibilityTest`
  PROOF-NEEDS.md: two list references `VeriSimVql` -> `VeriSimVcl`

Canonical name: VeriSim Consonance Language (VCL). Extension:
VCL-UT (VCL Usage-Tracked). File extension: `.vclut`.

Follow-on to idaptik commit 31dd4a7 (same-day, same sweep completion
for the idaptik-side Vql files).

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

Author: hyperpolymath

PROOF-NEEDS.md

@@ -6,7 +6,7 @@
 - **LOC**: ~94,700
 - **Languages**: Elixir, ReScript, Gleam, Julia, Rust, Idris2, Zig
 - **Existing ABI proofs**: `src/abi/*.idr` (template-level)
-- **Dangerous patterns**: 20+ `Obj.magic` in ReScript connector clients (VeriSimDrift, VeriSimFederation, VeriSimHexad, VeriSimProvenance, VeriSimSearch, VeriSimVql, Registry)
+- **Dangerous patterns**: 20+ `Obj.magic` in ReScript connector clients (VeriSimDrift, VeriSimFederation, VeriSimHexad, VeriSimProvenance, VeriSimSearch, VeriSimVcl, Registry)
 
 ## What Needs Proving
 
@@ -17,7 +17,7 @@
 
 ### Connector Client Type Safety (connectors/clients/rescript/)
 - Every client module uses `json->Obj.magic` to cast JSON responses to typed records
-- VeriSimDrift, VeriSimFederation, VeriSimHexad, VeriSimProvenance, VeriSimSearch, VeriSimVql all affected
+- VeriSimDrift, VeriSimFederation, VeriSimHexad, VeriSimProvenance, VeriSimSearch, VeriSimVcl all affected
 - Prove: API response schemas match expected ReScript types
 
 ### Registry / Consensus (src/registry/)

docs/backwards-compatibility.adoc

@@ -296,7 +296,7 @@ ENV VQL_VERSION="1.x"  # Auto-upgrade within major version
 
 ```elixir
 # test/vcl_compatibility_test.exs
-defmodule VeriSim.VQLCompatibilityTest do
+defmodule VeriSim.VCLCompatibilityTest do
   use ExUnit.Case
 
   @vcl_versions ["1.0.0", "1.1.0", "1.2.0"]