release: bump 0.9.5 -> 0.9.6 (#331)

Documentation release for the R binding. The library API and every indicator are
unchanged from `0.9.5`; only the R package's help pages change.

### What's in 0.9.6
- **R package documentation** (landed in #330): the twelve undocumented data-layer
  exports now have full man pages, the stale `AwesomeOscillatorHistogram` codoc is
  fixed, and a broken `push()` example is corrected — clearing the two `R CMD check`
  warnings r-universe reported for `0.9.5`. CI now runs `R CMD check` so doc drift
  fails the PR instead of reaching r-universe.

Pure version-string bump on top — `bump_version.py` touched 19 files. `cargo fmt`
clean.

Tag/publish waits for explicit GO (irreversible publish to crates.io / PyPI / npm
/ NuGet / Maven / Go / r-universe).

Cargo.lock

@@ -1785,7 +1785,7 @@ dependencies = [
 
 [[package]]
 name = "wickra"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "approx",
  "criterion",
@@ -1796,7 +1796,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-bench"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "criterion",
  "kand",
@@ -1808,7 +1808,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-c"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "tokio",
  "wickra-core",
@@ -1817,7 +1817,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-core"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "approx",
  "proptest",
@@ -1827,7 +1827,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-data"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "approx",
  "csv",
@@ -1846,7 +1846,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-examples"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "serde_json",
  "tokio",
@@ -1856,7 +1856,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-node"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "napi",
  "napi-build",
@@ -1868,7 +1868,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-python"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "bytemuck",
  "pyo3",
@@ -1879,7 +1879,7 @@ dependencies = [
 
 [[package]]
 name = "wickra-wasm"
-version = "0.9.5"
+version = "0.9.6"
 dependencies = [
  "console_error_panic_hook",
  "js-sys",