release: bump 0.4.7 -> 0.5.0 (#159)

Version bump for the 0.5.0 release, which ships the relicense to MIT OR Apache-2.0.

Stacked on #158 (base branch `chore/relicense-mit-apache`) so this PR's diff is the bump only. After #158 merges to main, GitHub retargets this PR to main; merge it, then tag `v0.5.0` to publish.

## Changes
- Bump 0.4.7 -> 0.5.0 across the Cargo workspace, Python `pyproject.toml`, Node `package.json` + 6 platform manifests + 2 lockfiles, and `Cargo.lock`.
- CHANGELOG: cut the [0.5.0] section (the relicense) and add compare URLs.
- SECURITY.md: supported versions 0.4.x -> 0.5.x.

Minor (not patch) bump: a relicense is a significant change. No code changes.

NOTE: do not tag/release until you give the go (irreversible publish to crates.io/PyPI/npm). Suggested merge order: #158 -> this -> tag `v0.5.0` -> then the downstream PRs.

Cargo.lock

@@ -1867,7 +1867,7 @@ dependencies = [
 
 [[package]]
 name = "wickra"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "approx",
  "criterion",
@@ -1878,7 +1878,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-core"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "approx",
  "proptest",
@@ -1888,7 +1888,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-data"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "approx",
  "csv",
@@ -1915,7 +1915,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-node"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "napi",
  "napi-build",
@@ -1925,7 +1925,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-python"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "numpy",
  "pyo3",
@@ -1934,7 +1934,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-wasm"
-version = "0.4.7"
+version = "0.5.0"
 dependencies = [
  "console_error_panic_hook",
  "js-sys",