v0.5.0a1 The Sentinel: plugin-enabled scanning, adaptive engine hardening, and preflight green

[PythonWoods-Dev]

Summary
This PR finalizes the Sentinel milestone for v0.5.0a1 by closing the remaining blocker and stabilizing runtime, performance, and release quality gates.

What was delivered
Plugin-enabled scanning (Safe Harbor fully implemented)
Added explicit plugin allowlist support in project configuration.
Rule loading is now deterministic:
Core rules are always active.
Custom regex rules are loaded from configuration.
External plugin rules are loaded only when explicitly listed.
Added robust core fallback behavior for environments where entry-point metadata is not available.
Parallel Phase B optimization
In the parallel + validate links path, Phase B now performs link collection without re-running rule checks.
This removes redundant compute and reduces overhead on larger documentation trees.
Robustness and UX improvements
Added clear fail-fast validation for worker values.
Updated scanner documentation text to match actual execution behavior and constraints.
Fixed final typing issue detected by mypy in preflight.
Quality and release readiness
Full preflight pipeline passes.
Test suite passes with coverage above required threshold.
Examples were verified end-to-end and classified by expected behavior.
Changelog and release-track messaging were aligned:
0.4.x documented as abandoned exploratory line.
0.5.x documented as active stabilization line.
Configuration and behavior impact
New plugin allowlist behavior enables strict user control over third-party rule activation.
Existing projects without plugin configuration continue to work with core rules enabled.
Invalid worker values now return immediate, clear validation errors.
Validation performed
nox preflight: pass
ruff check and format check: pass
mypy: pass
pytest: pass
coverage threshold: pass
Examples verification matrix
Example Result Expected Notes
examples/broken-docs Fail Fail Negative fixture with intentionally broken and unsafe links
examples/i18n-standard Pass Pass Healthy i18n fixture
examples/mkdocs-basic Pass Pass Healthy MkDocs baseline fixture
examples/security_lab Fail Fail Security fixture with traversal and absolute-path violations
examples/vanilla Pass Pass Healthy engine-agnostic fixture
examples/zensical-basic Pass Pass Healthy Zensical fixture
Examples status summary:

Expected Pass confirmed: 4 out of 4
Expected Fail confirmed: 2 out of 2

[Copilot]

Pull request overview

Finalizes the v0.5.0a1 “Sentinel” milestone by making rule/plugin scanning deterministic and allowlist-driven, tightening runtime validation, and reducing redundant work in the parallel + link-validation path.

Changes:

• Added plugins = [...] allowlist support to configuration and rule engine construction/loading.
• Optimized parallel “validate links” Phase B to collect links without re-running rule checks.
• Added fail-fast validation for invalid workers values and updated docs/changelog messaging accordingly.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/test_rules.py	Adds coverage for plugin allowlist behavior and no-op engine construction when unused.
tests/test_parallel.py	Adds regression test for clear workers validation error.
tests/test_integration_finale.py	Updates plugin listing tests to cover unloadable entry points and core fallback ordering.
tests/test_config.py	Adds parsing tests for plugins in zenzic.toml and pyproject.toml.
src/zenzic/models/config.py	Introduces ZenzicConfig.plugins allowlist field.
src/zenzic/core/scanner.py	Builds rule engine with core/custom/selected plugins; validates workers; Phase B avoids rule re-checks.
src/zenzic/core/rules.py	Adds PluginRegistry for discovery/loading and core fallback behavior; refactors list_plugin_rules().
README.md	Notes release-track clarification (0.4.x abandoned, 0.5.x stabilization).
README.it.md	Adds Italian release-track clarification note.
docs/it/about/index.md	Adds “Changelog” card and release-track policy blurb.
docs/about/index.md	Adds “Changelog” card and release-track policy blurb.
CHANGELOG.md	Documents new plugins config key and adds explicit “0.4.x (abandoned)” section.

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[Copilot]

load_selected_rules() preserves duplicates from plugin_ids (e.g., plugins = ["acme", "acme"]), which will load/instantiate the same entry point multiple times and can introduce unnecessary overhead or duplicated side effects. Consider de-duplicating requested while preserving order before resolving/loading entry points.

Suggested change

	requested = [pid.strip() for pid in plugin_ids if pid.strip()]
	requested: list[str] = []
	seen: set[str] = set()
	for pid in plugin_ids:
	cleaned = pid.strip()
	if cleaned and cleaned not in seen:
	seen.add(cleaned)
	requested.append(cleaned)

[Copilot]

Italian copy: "La linea 0.4.x e stata abbandonata; la stabilizzazione attiva e 0.5.x." is missing accents/grammar (e.g., "è stata", "è 0.5.x" / "è la 0.5.x"). Please correct to avoid typos in published docs.

Suggested change

	La linea 0.4.x e stata abbandonata; la stabilizzazione attiva e 0.5.x.
	La linea 0.4.x è stata abbandonata; la stabilizzazione attiva è la 0.5.x.