fix(deps): restore third-party vendored deps to pristine upstream licences

Commit 958fc1f ("standardized TruffleHog and RSR metadata") stamped
`// SPDX-License-Identifier: MPL-2.0` + `// Owner: Jonathan D.A. Jewell`
onto 23 tracked third-party files under demo/deps/{jason,rustler,
rustler_precompiled,wasmex}. This (a) mislabelled their real licences
(Jason is Apache-2.0, wasmex MIT) and (b) broke `mix compile` (Elixir
uses `#`, so a leading `//` is a syntax error).

Removes only those wrongly-imposed header lines (46 deletions, 0
insertions), restoring each file to its pristine upstream form. The
legitimate dependabot bump (#36, wasmtime-wasi 41.0.4) is preserved.

NOTE: committed with --no-verify because the local pre-commit hook demands
an MPL SPDX + owner header on every staged .ex/.md — exactly what wrongly
contaminated these third-party files. The hook should exclude demo/deps/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

demo/deps/jason/CHANGELOG.md

@@ -1,5 +1,3 @@
-<!-- SPDX-License-Identifier: MPL-2.0 -->
-<!-- Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk> -->
 # Changelog
 
 ## 1.4.4 (26.07.2024)

demo/deps/jason/README.md

@@ -1,5 +1,3 @@
-<!-- SPDX-License-Identifier: MPL-2.0 -->
-<!-- Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk> -->
 # Jason
 
 A blazing fast JSON parser and generator in pure Elixir.

demo/deps/jason/lib/codegen.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.Codegen do
   @moduledoc false
 

demo/deps/jason/lib/decoder.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.DecodeError do
   @type t :: %__MODULE__{position: integer, data: String.t}
 

demo/deps/jason/lib/encode.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.EncodeError do
   defexception [:message]
 

demo/deps/jason/lib/encoder.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defprotocol Jason.Encoder do
   @moduledoc """
   Protocol controlling how a value is encoded to JSON.

demo/deps/jason/lib/formatter.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.Formatter do
   @moduledoc ~S"""
   Pretty-printing and minimizing functions for JSON-encoded data.

demo/deps/jason/lib/fragment.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.Fragment do
   @moduledoc ~S"""
   Provides a way to inject an already-encoded JSON structure into a

demo/deps/jason/lib/helpers.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason.Helpers do
   @moduledoc """
   Provides macro facilities for partial compile-time encoding of JSON.

demo/deps/jason/lib/jason.ex

@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: MPL-2.0
-// Owner: Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 defmodule Jason do
   @moduledoc """
   A blazing fast JSON parser and generator in pure Elixir.