refactor(versions): honest labels and pin playwright in upgrade path

- Rename display sections: "Pinned Agent Tools" -> "Agent Tools
  (auto-upgraded by make versions-up)", toolchains and playwright
  sections note "pinned — edit versions.env to bump"
- Playwright stays pinned in version-upgrade.sh (uses $PLAYWRIGHT_VERSION
  not get_latest) — browser version bumps break test stability
- Playwright still in TOOL_REGISTRY for `make versions` comparison,
  so you can see when a newer version exists without auto-upgrading

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: lroolle

scripts/toolchain-report.sh

@@ -18,7 +18,7 @@ line() {
 main() {
     load_version_pins
 
-    heading "Pinned Toolchains"
+    heading "Toolchains (pinned — edit versions.env to bump)"
     line "Node.js line:" "${NODE_MAJOR}.x"
     line "Go:" "$GO_VERSION"
     line "Python:" "$PYTHON_VERSION"
@@ -28,15 +28,15 @@ main() {
     line "delta:" "$DELTA_VERSION"
     line "tmux:" "$TMUX_VERSION"
 
-    heading "Pinned Agent Tools"
+    heading "Agent Tools (auto-upgraded by make versions-up)"
     line "Claude Code:" "$CLAUDE_CODE_VERSION"
     line "Claude Trace:" "$CLAUDE_TRACE_VERSION"
     line "Codex:" "$CODEX_VERSION"
     line "Gemini CLI:" "$GEMINI_CLI_VERSION"
     line "Atlas CLI:" "$ATLAS_CLI_VERSION"
     line "Copilot API:" "$COPILOT_API_VERSION"
 
-    heading "Pinned Browser Tooling"
+    heading "Browser Tooling (pinned — edit versions.env to bump)"
     line "Playwright:" "$PLAYWRIGHT_VERSION"
 
     heading "Floating Build-Time Tools"

scripts/version-upgrade.sh

@@ -104,7 +104,7 @@ main() {
     gemini_ver="${_CLI_GEMINI:-$(get_latest "gemini-cli")}"
     atlas_ver="${_CLI_ATLAS:-$(get_latest "atlas-cli")}"
     copilot_ver="${_CLI_COPILOT:-$(get_latest "copilot-api")}"
-    playwright_ver="${_CLI_PLAYWRIGHT:-$(get_latest "playwright")}"
+    playwright_ver="${_CLI_PLAYWRIGHT:-${PLAYWRIGHT_VERSION}}"
 
     # Verify all required versions are set
     local missing=()