Release/v0.4.0

[ikelaiah]

PasWeave v0.4.0

PasWeave v0.4.0 turns generated documentation into authoring feedback that can
be used in CI. It validates structured directives against parsed signatures,
keeps project-local reference links honest, and emits stable coded diagnostics
from the shared documentation model.

Highlights:

• stable warning and error codes, including parameter, return, reference,
  generated-route, and coverage diagnostics;
• parsed-signature validation for missing, duplicate, and unknown @param
  entries plus invalid or conflicting @returns directives;
• conservative model-level @see resolution across the current unit and its
  documented interface dependencies, with unresolved targets left unlinked;
• generated-anchor and unit-route integrity checks before output;
• a deterministic diagnostics.json artifact alongside api-model.json;
• --min-documentation-coverage and --fail-on=warning CI controls while
  retaining error-only failure by default; and
• regression fixtures for ///, { ... }, and (* ... *) comment forms.

See authoring feedback and reference integrity
for the diagnostic contract and CI examples.

Validation includes the complete fixture suite, CLI checks for default and CI
failure policies, and a 45-unit mathlib-fp audit that generated 2,338
symbols with zero errors. Its 2,676 missing-parameter warnings demonstrate
why warning-level failure remains an explicit CI choice.