docs(deps[gp-sphinx]) bump 0.0.1a17 → 0.0.1a18.dev0

why: gp-sphinx 0.0.1a18.dev0 ships the curated autodoc rendering
work from PR git-pull/gp-sphinx#36 — default-value source text,
identifier cross-references in parameter signatures, canonical
field-list xrefs, responsive autodoc layout, and a workspace-wide
linkcode_resolve factory.

what:
- bump every gp-sphinx workspace pin in pyproject.toml + uv.lock
- add [tool.uv].prerelease = "allow" so uv resolves the *.dev0 pins

Author: tony

pyproject.toml

@@ -64,9 +64,9 @@ Changes = "https://github.com/vcs-python/libvcs/blob/master/CHANGES"
 [dependency-groups]
 dev = [
   # Docs
-  "gp-sphinx==0.0.1a17",
-  "sphinx-autodoc-api-style==0.0.1a17",
-  "sphinx-autodoc-pytest-fixtures==0.0.1a17",
+  "gp-sphinx==0.0.1a18.dev0",
+  "sphinx-autodoc-api-style==0.0.1a18.dev0",
+  "sphinx-autodoc-pytest-fixtures==0.0.1a18.dev0",
   "gp-libs",
   "sphinx-autobuild",
   # Testing
@@ -85,9 +85,9 @@ dev = [
 ]
 
 docs = [
-  "gp-sphinx==0.0.1a17",
-  "sphinx-autodoc-api-style==0.0.1a17",
-  "sphinx-autodoc-pytest-fixtures==0.0.1a17",
+  "gp-sphinx==0.0.1a18.dev0",
+  "sphinx-autodoc-api-style==0.0.1a18.dev0",
+  "sphinx-autodoc-pytest-fixtures==0.0.1a18.dev0",
   "gp-libs",
   "sphinx-autobuild",
 ]
@@ -115,6 +115,13 @@ libvcs = "libvcs.pytest_plugin"
 requires = ["hatchling"]
 build-backend = "hatchling.build"
 
+[tool.uv]
+# `[DO NOT MERGE]`: gp-sphinx workspace ships on the 0.0.1a18.devN
+# pre-release track until PR git-pull/gp-sphinx#36 is proven
+# end-to-end. uv otherwise refuses to resolve `*.dev0` markers
+# without this allow.
+prerelease = "allow"
+
 [tool.uv.exclude-newer-package]
 # git-pull packages release in lockstep with their workspaces, so a
 # fresh release blocking on the 3-day cooldown blocks every